Aqueous methods for titanating a chromium/silica catalyst with an alkali metal

ABSTRACT

Methods for making titanated silica supports, titanated chromium/silica pre-catalysts, and activated titanated chromium/silica catalysts are disclosed in which hydrogen peroxide and an alkali metal precursor are used during catalyst preparation. Resulting titanated chromium/silica pre-catalysts often contain silica, 0.1 to 5 wt. % chromium, 0.1 to 10 wt. % titanium, and less than or equal to 4 wt. % carbon, and further contain an alkali metal or zinc at a molar ratio of alkali metal:titanium or zinc:titanium from 0.02:1 to 3:1 and/or at an amount in a range from 0.01 to 2 mmol of alkali metal or zinc per gram of the silica. High melt index potential activated titanated chromium/silica catalysts can be used to polymerize olefins to produce, for example, ethylene based homopolymers and copolymers having HLMI values of greater than 30 g/10 min.

REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 63/334,741, filed on Apr. 26, 2022, the disclosure ofwhich is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure generally relates to titanated chromiumcatalysts, methods for preparing the titanated chromium catalysts,methods for using the titanated chromium catalysts to polymerizeolefins, the polymer resins produced using such chromium catalysts, andarticles produced using these polymer resins. More particularly, thepresent disclosure relates to aqueous methods for making titanatedchromium catalysts in which an alkali metal is utilized during catalystpreparation.

BACKGROUND OF THE INVENTION

Chromium/silica catalysts can be used to produce HDPE. The addition oftitanium to chromium/silica can increase the activity of the catalyst,but more importantly, can increase the melt index potential of thecatalyst, i.e., the ability of the catalyst to produce higher melt indexor higher melt flow polymers. Often, titanium addition has beenaccomplished via an anhydrous route, using a titanium precursor andimpregnation onto chromium/silica using a suitable organic solvent, suchas a hydrocarbon, an alcohol, or an ether. The presence of organics,unfortunately, can result in high Volatile Organic Compound (VOC)emissions during the preparation, activation, and processing oftitanated chromium catalysts. Water-based alternatives are available,but often suffer from poor titanium efficiency and non-uniformincorporation. In view of these drawbacks, it would be beneficial toprovide improved methods for making titanated chromium catalysts.Accordingly, it is to this end that the present invention is generallydirected.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify required oressential features of the claimed subject matter. Nor is this summaryintended to be used to limit the scope of the claimed subject matter.

In one aspect of this invention, a titanated silica support isdisclosed, and in this aspect, the titanated silica support can comprisesilica, from 0.1 to 10 wt. % titanium, from 0.5 to 12 wt. % water, lessthan or equal to 2 wt. % carbon, and an alkali metal and/or zinc at amolar ratio of alkali metal:titanium or zinc:titanium from 0.02:1 to 3:1and/or at an amount in a range from 0.01 to 2 mmol of alkali metal orzinc per gram of the silica.

In another aspect of this invention, a titanated chromium/silicapre-catalyst is disclosed, and in this aspect, the titanatedchromium/silica pre-catalyst can comprise silica, from 0.1 to 5 wt. %chromium, from 0.1 to 10 wt. % titanium, from 0.5 to 12 wt. % water,less than or equal to 4 wt. % carbon, and an alkali metal and/or zinc ata molar ratio of alkali metal:titanium or zinc:titanium from 0.02:1 to3:1 and/or at an amount in a range from 0.01 to 2 mmol of alkali metalor zinc per gram of the silica.

In yet another aspect, a titanated chromium/silica catalyst isdisclosed, and in this aspect, the titanated chromium/silica catalystcan comprise silica, from 0.1 to 5 wt. % chromium, from 0.1 to 10 wt. %titanium, and an alkali metal and/or zinc at a molar ratio of alkalimetal:titanium or zinc:titanium from 0.02:1 to 3:1 and/or at an amountin a range from 0.01 to 2 mmol of alkali metal or zinc per gram of thesilica, wherein at least 60 wt. % of the chromium is present in anoxidation state of +6. In still another aspect, the titanatedchromium/silica catalyst can comprise silica, from 0.1 to 5 wt. %chromium, and from 0.1 to 10 wt. % titanium, wherein at least 60 wt. %of the chromium is present in an oxidation state of +6, and the catalystis characterized by a HLMI (g/10 min) of the polymer that is greaterthan the equation Y (HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983), whereinx is the number of titanium atoms per square nanometer of silica surfacearea for the titanated chromium/silica catalyst.

The present invention also contemplates and encompasses olefinpolymerization processes. Such processes can comprise contacting any ofthe (activated) titanated chromium/silica catalysts disclosed herein andan optional co-catalyst with an olefin monomer and an optional olefincomonomer in a polymerization reactor system under polymerizationconditions to produce an olefin polymer. Beneficially, the titanatedchromium/silica catalysts have high melt index potential, allowing theproduction of olefin polymers having higher melt indices (lowermolecular weights), but with less titanium present in the catalyst.

Processes for preparing the titanated silica supports and subsequentchromium catalysts also are described herein. A process for preparing atitanated silica support can include the steps of (i) contacting water,a peroxide compound, and a titanium precursor to form a first mixture,(ii) contacting a silica with the first mixture under conditionssufficient for titanium to adsorb onto the silica and form a secondmixture, (iii) isolating a solid fraction from the second mixture, and(iv) drying the solid fraction to form the titanated silica support.Several variations of this process also are provided herein. Titanatedchromium/silica pre-catalysts can be prepared by using the same generalprocesses, but impregnating the silica support with a chromium precursorat an appropriate step in the respective process. Subsequently, the(activated) titanated chromium/silica catalyst can be prepared byactivating the titanated chromium/silica pre-catalyst under suitableactivation conditions.

Both the foregoing summary and the following detailed descriptionprovide examples and are explanatory only. Accordingly, the foregoingsummary and the following detailed description should not be consideredto be restrictive. Further, features or variations may be provided inaddition to those set forth herein. For example, certain aspects may bedirected to various feature combinations and sub-combinations describedin the detailed description.

BRIEF DESCRIPTION OF THE FIGURE

The following FIGURE forms part of the present specification and isincluded to further demonstrate certain aspects of the presentinvention. The invention may be better understood by reference to thisFIGURE in combination with the detailed description.

FIG. 1 presents a plot of the HLMI of the polymer versus the number oftitanium atoms per square nanometer for the control group of titanatedchromium/silica catalysts and for the titanated chromium/silicacatalysts of Examples 28-41.

While the inventions disclosed herein are susceptible to variousmodifications and alternative forms, only a few specific aspects havebeen shown by way of example in the drawing and described in detailbelow. The FIGURE and detailed description of specific aspects are notintended to limit the breadth or scope of the inventive concepts or theappended claims in any manner. Rather, the FIGURE and detaileddescription are provided to illustrate the inventive concepts to aperson of ordinary skill in the art and to enable such person to makeand use the inventive concepts.

Definitions

To define more clearly the terms used herein, the following definitionsare provided. Unless otherwise indicated, the following definitions areapplicable to this disclosure. If a term is used in this disclosure butis not specifically defined herein, the definition from the IUPACCompendium of Chemical Terminology, 2^(nd) Ed (1997), can be applied, aslong as that definition does not conflict with any other disclosure ordefinition applied herein, or render indefinite or non-enabled any claimto which that definition is applied. To the extent that any definitionor usage provided by any document incorporated herein by referenceconflicts with the definition or usage provided herein, the definitionor usage provided herein controls.

Herein, features of the subject matter are described such that, withinparticular aspects, a combination of different features can beenvisioned. For each and every aspect and each and every featuredisclosed herein, all combinations that do not detrimentally affect thecompounds, compositions, processes, or methods described herein arecontemplated with or without explicit description of the particularcombination. Additionally, unless explicitly recited otherwise, anyaspect or feature disclosed herein can be combined to describe inventivecompounds, compositions, processes, or methods consistent with thepresent disclosure.

Generally, groups of elements are indicated using the numbering schemeindicated in the version of the periodic table of elements published inChemical and Engineering News, 63(5), 27, 1985. In some instances, agroup of elements can be indicated using a common name assigned to thegroup; for example, alkali metals for Group 1 elements, alkaline earthmetals for Group 2 elements, transition metals for Group 3-12 elements,and halogens or halides for Group 17 elements.

For any particular compound or group disclosed herein, any name orstructure (general or specific) presented is intended to encompass allconformational isomers, regioisomers, stereoisomers, and mixturesthereof that can arise from a particular set of substituents, unlessotherwise specified. The name or structure (general or specific) alsoencompasses all enantiomers, diastereomers, and other optical isomers(if there are any) whether in enantiomeric or racemic forms, as well asmixtures of stereoisomers, as would be recognized by a skilled artisan,unless otherwise specified. For instance, a general reference to pentaneincludes n-pentane, 2-methyl-butane, and 2,2-dimethylpropane; and ageneral reference to a butyl group includes a n-butyl group, a sec-butylgroup, an iso-butyl group, and a t-butyl group.

The terms “contacting” and “combining” are used herein to describecompositions, processes, and methods in which the materials orcomponents are contacted or combined together in any order, in anymanner, and for any length of time, unless otherwise specified.

For example, the materials or components can be blended, mixed,slurried, dissolved, reacted, treated, compounded, or otherwisecontacted or combined in some other manner or by any suitable method ortechnique.

In this disclosure, while compositions, processes, and methods aredescribed in terms of “comprising” various components or steps, thecompositions, processes, and methods also can “consist essentially of”or “consist of” the various components or steps, unless statedotherwise.

The terms “a,” “an,” “the,” etc., are intended to include pluralalternatives, e.g., at least one, unless otherwise specified. Forinstance, the disclosure of “a reactor” or “a comonomer” is meant toencompass one, or combinations of more than one, reactor or comonomer,respectively, unless otherwise specified.

The term “polymer” is used herein generically to include olefinhomopolymers, copolymers, terpolymers, and the like, as well as alloysand blends thereof. The term “polymer” also includes impact, block,graft, random, and alternating copolymers. A copolymer can be derivedfrom an olefin monomer and one olefin comonomer, while a terpolymer canbe derived from an olefin monomer and two olefin comonomers.Accordingly, “polymer” encompasses copolymers and terpolymers.Similarly, the scope of the term “polymerization” includeshomopolymerization, copolymerization, and terpolymerization. Therefore,an ethylene polymer includes ethylene homopolymers, ethylene copolymers(e.g., ethylene/α-olefin copolymers), ethylene terpolymers, and thelike, as well as blends or mixtures thereof. Thus, an ethylene polymerencompasses polymers often referred to in the art as LLDPE (linear lowdensity polyethylene) and HDPE (high density polyethylene). As anexample, an ethylene copolymer can be derived from ethylene and acomonomer, such as 1-butene, 1-hexene, or 1-octene. If the monomer andcomonomer are ethylene and 1-hexene, respectively, the resulting polymercan be categorized an as ethylene/1-hexene copolymer. The term “polymer”also includes all possible geometrical configurations, if present andunless stated otherwise, and such configurations can include isotactic,syndiotactic, and random symmetries. The term “polymer” also is meant toinclude all molecular weight polymers.

The terms “catalyst composition,” “catalyst mixture,” “catalyst system,”and the like, do not depend upon the actual product or compositionresulting from the contact or reaction of the initial components of thedisclosed or claimed catalyst composition/mixture/system, the nature ofthe active catalytic site, or the fate of the co-catalyst or thetitanated chromium catalyst after combining these components. Therefore,the terms “catalyst composition,” “catalyst mixture,” “catalyst system,”and the like, encompass the initial starting components of thecomposition, as well as whatever product(s) may result from contactingthese initial starting components, and this is inclusive of bothheterogeneous and homogenous catalyst systems or compositions. The terms“catalyst composition,” “catalyst mixture,” “catalyst system,” and thelike, may be used interchangeably throughout this disclosure.

Several types of ranges are disclosed in the present invention. When arange of any type is disclosed or claimed, the intent is to disclose orclaim individually each possible number that such a range couldreasonably encompass, including end points of the range as well as anysub-ranges and combinations of sub-ranges encompassed therein. As arepresentative example, the chromium content of the pre-catalyst orcatalyst can be in certain ranges in various aspects of this invention.By a disclosure that the pre-catalyst or catalyst contains from 0.1 to 5wt. % chromium, the intent is to recite that the chromium content can beany amount in the range and, for example, can include any range orcombination of ranges from 0.1 to 5 wt. % chromium, such as from 0.3 to3 wt. %, from 0.4 to 2 wt. %, from 0.5 to 1.5 wt. %, or from 0.7 to 1.5wt. %, and so forth. Likewise, all other ranges disclosed herein shouldbe interpreted in a manner similar to this example.

In general, an amount, size, formulation, parameter, range, or otherquantity or characteristic is “about” or “approximate” whether or notexpressly stated to be such. Whether or not modified by the term “about”or “approximately,” the claims include equivalents to the quantities orcharacteristics.

Although any methods, devices, and materials similar or equivalent tothose described herein can be used in the practice or testing of theinvention, the typical methods, devices, and materials are hereindescribed.

All publications and patents mentioned herein are incorporated herein byreference in their entirety for the purpose of describing anddisclosing, for example, the constructs and methodologies that aredescribed in the publications and patents, which might be used inconnection with the presently described invention.

DETAILED DESCRIPTION OF THE INVENTION

Disclosed herein are processes for preparing titanated silica supportsand titanated chromium/silica pre-catalysts and activated catalysts.Advantageously, a peroxide compound and/or an alkali metal is/arepresent during the steps used to prepare these supports and catalystmaterials, which results in a significant and unexpected increase in themelt index potential of the titanated chromium catalyst. While notwishing to be bound by the following theory, it is believed that thedisclosed methods result in more uniform titanium incorporation and moreefficient titanium usage, as well as adsorption of the titanium onto thesilica support, so less titanium is needed to achieve a desired HLMI ofthe resultant polymer. Further, it is also believed that the titanium isevenly distributed amongst all particle sizes, instead of a widedistribution of titanium content depending upon the relative sizes—smallor large—of the catalyst particles.

Titanated Silica Supports and Titanated Chromium Catalysts

A representative and non-limiting example of a titanated silica supportconsistent with this invention can comprise silica, from 0.1 to 10 wt. %titanium, from 0.5 to 12 wt. % water, less than or equal to 2 wt. %carbon, and an alkali metal and/or zinc at a molar ratio of alkalimetal:titanium or zinc:titanium from 0.02:1 to 3:1 and/or at an amountin a range from 0.01 to 2 mmol of alkali metal or zinc per gram of thesilica. Related to these titanated silica supports are titanatedchromium/silica pre-catalysts, an example of which can comprise silica,from 0.1 to 5 wt. % chromium, from 0.1 to 10 wt. % titanium, from 0.5 to12 wt. % water, less than or equal to 4 wt. % carbon, and an alkalimetal and/or zinc at a molar ratio of alkali metal:titanium orzinc:titanium from 0.02:1 to 3:1 and/or at an amount in a range from0.01 to 2 mmol of alkali metal or zinc per gram of the silica. Herein, a“pre-catalyst” is meant to indicate that the catalyst has not beenactivated or calcinated, which process converts all or a large portionof the lower oxidation state chromium to an oxidation state of +6(hexavalent chromium). Referring now to this titanated chromium/silicapre-catalyst, at least 75 wt. % of the chromium often is present in anoxidation state of three or less. In some aspects, at least 80 wt. %, orat least 90 wt. %, or at least 95 wt. %, or all or substantially all, ofthe chromium of the pre-catalyst can be present in an oxidation state ofthree or less.

Beneficially, there can be substantially no VOC's (volatile organiccompounds) emitted during a thermal treatment (e.g., calcination oractivation) step. For instance, there can be substantially no VOC'semitted during calcination or activation of the titanatedchromium/silica pre-catalyst (or the titanated silica support). Thus, inaccordance with certain aspects of this invention, the titanatedchromium/silica pre-catalyst (or the titanated silica support) cancontain less than or equal to 3 wt. % carbon, less than or equal to 2wt. % carbon, or less than or equal to 1 wt. % carbon, and in someinstances, less than or equal to 0.5 wt. % carbon, less than or equal to0.3 wt. % carbon, or less than or equal to 0.1 wt. % carbon. Theseweight percentages are based on the amount of carbon (by weight)relative to the total weight of the respective pre-catalyst or support,and can be determined via CHN analysis.

The titanated chromium/silica pre-catalyst and the titanated silicasupport are generally in the form of free-flowing powders orparticulates. Nonetheless, these titanated chromium/silica pre-catalystand titanated silica support materials can contain entrainedwater/moisture, such that on a weight basis, the titanatedchromium/silica pre-catalyst and the titanated silica support,independently, can contain from 0.5 to 12 wt. % water/moisture. Moreoften, the amount of water/moisture ranges from 1 to 11 wt. %, from 2.5to 10 wt. %, from 3 to 9 wt. %, or from 5 to 8 wt. %. These weightpercentages are based on the amount of water/moisture relative to thetotal weight of the respective pre-catalyst or support, and can bedetermined using thermogravimetric analysis (TGA).

A representative and non-limiting example of a titanated chromium/silicacatalyst consistent with this invention can comprise silica, from 0.1 to5 wt. % chromium, from 0.1 to 10 wt. % titanium, and an alkali metaland/or zinc at a molar ratio of alkali metal:titanium or zinc:titaniumfrom 0.02:1 to 3:1 and/or at an amount in a range from 0.01 to 2 mmol ofalkali metal or zinc per gram of the silica, wherein at least 60 wt. %of the chromium is present in an oxidation state of +6. Anothernon-limiting example of a representative titanated chromium/silicacatalyst of this invention can comprise silica, from 0.1 to 5 wt. %chromium, and from 0.1 to 10 wt. % titanium, wherein at least 60 wt. %of the chromium is present in an oxidation state of +6, and the catalystis characterized by a HLMI (g/10 min) of the polymer that is greaterthan the equation Y (HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983), whereinx is the number of titanium atoms per square nanometer of silica surfacearea for the titanated chromium/silica catalyst. Herein, the “catalyst”is distinguished from the “pre-catalyst” and is meant to indicate thatthe catalyst has been activated or calcinated (an activated catalyst),thus all or a large portion of lower oxidation state chromium has beenconverted to an oxidation state of +6 (hexavalent chromium). Hence, the“catalyst” can be formed by activating or calcining the “pre-catalyst.”

As it pertains to this titanated chromium/silica catalyst, at least 60wt. % of the chromium is present in an oxidation state of +6. In oneaspect, at least 70 wt. %, at least 75 wt. % in another aspect, at least80 wt. % in another aspect, at least 85 wt. % in another aspect, atleast 90 wt. % in yet another aspect, and at least 95 wt. % in stillanother aspect, of the chromium of the titanated chromium/silicacatalyst can be present in an oxidation state of +6. The amount ofCr(VI) can be determined by mixing 2 g of the catalyst with 20 mL of asolution of 2 M H₂SO₄, then adding 5 drops of ferroin Fe(+3) indicator.This usually turns the mixture a blue-green color indicating thepresence of Fe(III) ions. Next, the mixture is titrated to the ferroinendpoint (red color) using a solution of ferrous ammonium sulfate, whichhas been previously calibrated by reaction with a standardized 0.1 Msodium dichromate solution. When the mixture turns red, the end point isreached, the titrant volume is recorded, and the oxidation capacity ofthe catalyst is calculated and expressed as wt. % Cr(VI).

After calcining/activating, there is generally very littlewater/moisture present on the titanated chromium/silica catalyst, forinstance, less than or equal to 3 wt. % water/moisture, based on thetotal weight of the catalyst. More often, the titanated chromium/silicacatalyst has a water/moisture content of less than or equal to 2 wt. %,less than or equal to 1.5 wt. %, less than or equal to 1 wt. %, or lessthan or equal to 0.5 wt. %, and the like. The disclosed titanatedchromium/silica catalysts also can contain an alkali metal and/or zincat a molar ratio of alkali metal:titanium or zinc:titanium from 0.02:1to 3:1, or also can contain an alkali metal and/or zinc at an amount ina range from 0.01 to 2 mmol of alkali metal or zinc per gram of thesilica, or both.

In an aspect, the titanated chromium/silica catalyst can becharacterized as having a melt index potential (MIP) of, that is byproducing a polymer of, HLMI (g/10 min) that is greater than theequation Y (HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983), wherein x is thenumber of titanium atoms per square nanometer of silica surface area forthe titanated chromium/silica catalyst. This is illustrated graphicallyin FIG. 1 , and discussed further in the examples that follow. In someaspects, the titanated chromium/silica catalyst can be characterized bya HLMI (g/10 min) of the polymer that is greater thanY=1.1*(−9.6153x³+21.088x²+25.835x+5.7983); alternatively,Y=1.15*(−9.6153x³+21.088x²+25.835x+5.7983); alternatively,Y=1.2*(−9.6153x³+21.088x²+25.835x+5.7983); or alternatively,Y=1.3*(−9.6153x³+21.088x²+25.835x+5.7983). As it pertains to theseequations, generally, the pore volume of the catalyst is less than orequal to 2.2, 2.0, 1.8 or 1.6 mL/g; the catalyst is activated/calcinedfor 3 hr in dry air at 650° C.; and the polymer produced in isobutanediluent at 105° C. and 550 psig (3792 kPa) ethylene pressure, at aproductivity of ˜3000 g polymer/g catalyst (e.g., at least 2500, 2800,3000, or 3200 g polymer/g catalyst).

The amount of chromium in the titanated chromium/silica pre-catalystsand titanated chromium/silica catalysts disclosed herein is notparticularly limited. Generally, however, the amount of chromium in therespective pre-catalyst or catalyst can range from 0.1 to 5 wt. %;alternatively, from 0.3 to 3 wt. %; alternatively, from 0.4 to 2 wt. %;alternatively, from 0.5 to 1.5 wt. %; or alternatively, from 0.7 to 1.5wt. %. These weight percentages are based on the amount of chromiumrelative to the total weight of the respective pre-catalyst or catalyst.

Referring now to the titanated silica support, the titanatedchromium/silica pre-catalyst, and the titanated chromium/silicacatalyst, the amount of titanium present also is not particularlylimited. Generally, however, the amount of titanium in the respectivesupport, pre-catalyst, or catalyst can range from 0.1 to 10 wt. %;alternatively, from 0.5 to 7 wt. %; alternatively, from 0.5 to 3 wt. %;alternatively, from 0.8 to 2 wt. %; alternatively, from 1 to 6 wt. %; oralternatively, from 1.5 to 4 wt. %. These weight percentages are basedon the amount of titanium relative to the total weight of the respectivesupport, pre-catalyst, or catalyst. As disclosed herein, due to thecatalyst preparation processes utilizing alkali metals (or zinc) andperoxides, lower titanium loadings are needed to achieve a particularHLMI value of the resultant polymer, as compared to traditionaltitanated chromium catalysts.

The alkali metal or zinc is a very minor component of the support orcatalyst, although its impact on catalyst performance is verysignificant. The respective support, pre-catalyst, or catalyst containsany suitable amount of the alkali metal or zinc, often at a minimummolar ratio of alkali metal:titanium or zinc:titanium of 0.02:1, 0.05:1,0.08:1, 0.1:1, 0.12:1, 0.15:1, or 0.2:1, and additionally oralternatively, a maximum molar ratio of 3:1, 2.5:1, 2.2:1, 2:1, or1.8:1. Generally, the molar ratio of alkali metal:titanium orzinc:titanium can range from any minimum molar ratio to any maximummolar ratio described herein. For instance, representative andnon-limiting examples of suitable ranges for the molar ratio includefrom 0.02:1 to 3:1, from 0.08:1 to 3:1, from 0.1:1 to 3:1, from 0.12:1to 3:1, from 0.2:1 to 3:1, from 0.02:1 to 2.5:1, from 0.05:1 to 2.5:1,from 0.12:1 to 2.5:1, from 0.15:1 to 2.5:1, from 0.05:1 to 2.2:1, from0.1:1 to 2.2:1, from 0.2:1 to 2.2:1, from 0.02:1 to 2:1, from 0.05:1 to2:1, from 0.1:1 to 2:1, from 0.12:1 to 2:1, from 0.15:1 to 2:1, from0.2:1 to 2:1, from 0.02:1 to 1.8:1, from 0.08:1 to 1.8:1, from 0.1:1 to1.8:1, from 0.12:1 to 1.8:1, from 0.15:1 to 1.8:1, or from 0.2:1 to1.8:1. This molar ratio is determined by ICP analysis.

Additionally or alternatively, the respective support, pre-catalyst, orcatalyst contains any suitable amount of the alkali metal or zinc, oftenat a minimum amount of the alkali metal or zinc per gram of silica of0.01, 0.02, 0.04, 0.08, 0.1, 0.11, 0.13, or 0.15 mmol/g, andadditionally or alternatively, a maximum amount of 2, 1.5, 1.2, 1, 0.9,or 0.8 mmol/g. Generally, the amount of the alkali metal or zinc canrange from any minimum amount in mmol/g to any maximum amount in mmol/gdescribed herein. For instance, representative and non-limiting examplesof suitable ranges for the amount of alkali metal or zinc (mmol/g)include from 0.01 to 2, from 0.02 to 2, from 0.08 to 2, from 0.1 to 2,from 0.11 to 2, from 0.13 to 2, from 0.15 to 2, from 0.01 to 1.5, from0.04 to 1.5, from 0.11 to 1.5, from 0.01 to 1.2, from 0.04 to 1.2, from0.1 to 1.2, from 0.11 to 1.2, from 0.15 to 1.2, from 0.01 to 1, from0.04 to 1, from 0.08 to 1, from 0.1 to 1, from 0.11 to 1, from 0.13 to1, from 0.15 to 1, from 0.02 to 0.9, from 0.08 to 0.9, from 0.11 to 0.9,from 0.15 to 0.9, from 0.01 to 0.8, from 0.02 to 0.8, from 0.04 to 0.8,from 0.1 to 0.8, from 0.11 to 0.8, or from 0.13 to 0.8 mmol/g. Thealkali metal (or zinc) content is based on the mmol of the alkali metal(or zinc) versus the total weight of the silica in the respectivesupport, pre-catalyst, or catalyst (in grams). This is determined viaICP analysis.

In one aspect, the support, pre-catalyst, or catalyst can contain thealkali metal, and in another aspect, the support, pre-catalyst, orcatalyst can contain zinc. The alkali metal present on the respectivesupport, pre-catalyst, or catalyst can be (or can comprise) cesium,lithium, sodium, or potassium, as well as any combination thereof. Thus,the alkali metal can be (or can comprise) lithium; alternatively,sodium; or alternatively, potassium. It is unexpected that the presenceof alkali metals on the pre-catalyst and catalyst, particularly at theamounts noted above, does not destroy the catalyst activity, sincesodium and other such metals are typically catalyst poisons.

Nitrogen also can be present on the respective support, pre-catalyst, orcatalyst, depending upon the nature of the materials used duringcatalyst preparation and the chromium source/precursor, among otherfactors. While not limited thereto, the respective support,pre-catalyst, or catalyst can contain from 0.01 to 1.5 wt. % N, such asfrom 0.1 to 1.5 wt. %, from 0.3 to 1 wt. %, from 0.4 to 1.2 wt. %, from0.4 to 1 wt. %, or from 0.5 to 0.7 wt. % N, and the like. These weightpercentages are based on the total weight of the respective support,pre-catalyst, or catalyst, and can be determined via CHN analysis.

By weight, the vast majority of the respective support, pre-catalyst, orcatalyst is silica, often at least 70 wt. %, at least 80 wt. %, at least85 wt. %, or at least 90 wt. %. Illustrative and non-limiting ranges forthe amount of silica of the respective support, pre-catalyst, orcatalyst include from 70 to 99.5 wt. %, from 80 to 98 wt. %, from 80 to95 wt. %, from 85 to 98 wt. %, from 85 to 95 wt. %, from 90 to 99.5 wt.%, or from 90 to 98 wt. %, and the like.

The pore volumes of the titanated silica support, the titanatedchromium/silica pre-catalyst, and the titanated chromium/silica catalystare not particularly limited. For instance, the respective support,pre-catalyst, or catalyst can have a pore volume (total pore volume vianitrogen sorption) in a range from 0.5 to 3 mL/g, from 0.8 to 2.5 mL/g,from 1 to 2 mL/g, or from 1.3 to 1.8 mL/g, and so forth. Likewise, thesurface areas of the titanated silica support, the titanatedchromium/silica pre-catalyst, and the titanated chromium/silica catalystare not limited to any particular range. Generally, however, therespective support, pre-catalyst, or catalyst can have a BET surfacearea in a range from 100 to 700 m²/g, from 150 to 650 m²/g, from 200 to600 m²/g, or from 250 to 550 m²/g, and the like.

The titanated silica support, the titanated chromium/silicapre-catalyst, and the titanated chromium/silica catalyst can have anysuitable particle size, as would be recognized by those of skill in theart. Illustrative and non-limiting ranges for the average (d50) particlesize of the respective support, pre-catalyst, or catalyst can includefrom 15 to 350 μm, from 25 to 300 μm, from 40 to 120 μm, from 50 to 200μm, or from 75 to 150 μm.

Unexpectedly, and unlike other aqueous based catalyst preparationprocedures, the titanium is adsorbed onto the silica for the disclosedsupports, pre-catalysts, and catalysts. The adsorbed titanium and thecolor changes observed during catalyst preparation are described in theexamples that follow.

Also, for the disclosed supports, pre-catalysts, and catalysts, at leasta portion of the zinc or the alkali metal is bound (chemically) to thetitanium. For instance, while not being bound by theory, it is believedthat at least a portion of the sodium (or other alkali metal, or zinc)is bound to the titanium through an oxygen atom. Additionally oralternatively, at least a portion of the zinc and the titanium ispresent as zinc titanate and/or at least a portion of the alkali metaland the titanium is present as an alkali metal titanate, one example ofwhich is sodium titanate. These features can be determined usingsuitable analytical techniques such as XPS and XRD.

Polymerization Processes

Titanated chromium/silica catalysts (activated) of the present inventioncan be used to polymerize olefins to form homopolymers, copolymers,terpolymers, and the like. One such process for polymerizing olefins cancomprise contacting any (activated) titanated chromium/silica catalystdisclosed herein (e.g., produced by any process disclosed herein) and anoptional co-catalyst with an olefin monomer and an optional olefincomonomer in a polymerization reactor system under polymerizationconditions to produce an olefin polymer.

The polymerization processes disclosed herein often can employ aco-catalyst. In some aspects, the co-catalyst can comprise a metalhydrocarbyl compound, examples of which include non-halide metalhydrocarbyl compounds, metal hydrocarbyl halide compounds, non-halidemetal alkyl compounds, metal alkyl halide compounds, and so forth, andin which the metal can be any suitable metal, often a group 13 metal.Hence, the metal can be boron or aluminum in certain aspects of thisinvention, and the co-catalyst can comprise a boron hydrocarbyl oralkyl, or an aluminum hydrocarbyl or alkyl, as well as combinationsthereof.

In one aspect, the co-catalyst can comprise an aluminoxane compound, anorganoaluminum compound, or an organoboron compound, and this includescombinations of more than one co-catalyst compound. Representative andnon-limiting examples of aluminoxanes include methylaluminoxane,modified methylaluminoxane, ethylaluminoxane, n-propylaluminoxane,iso-propylaluminoxane, n-butylaluminoxane, t-butylaluminoxane,sec-butylaluminoxane, iso-butylaluminoxane, 1-pentylaluminoxane,2-pentylaluminoxane, 3-pentylaluminoxane, isopentylaluminoxane,neopentylaluminoxane, and the like, or any combination thereof.Representative and non-limiting examples of organoaluminums includetrimethylaluminum, triethylaluminum, tri-n-propylaluminum,tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum,tri-n-octylaluminum, diisobutylaluminum hydride, diethylaluminumethoxide, diethylaluminum chloride, and the like, or any combinationthereof. Representative and non-limiting examples of organoboronsinclude tri-n-butyl borane, tripropylborane, triethylborane, and thelike, or any combination thereof. Co-catalysts that can be used with thecatalysts of this invention are not limited to the co-catalystsdescribed above. Other suitable co-catalysts (such as organomagnesiumsand organolithiums) are well known to those of skill in the artincluding, for example, those disclosed in U.S. Pat. Nos. 3,242,099,4,794,096, 4,808,561, 5,576,259, 5,807,938, 5,919,983, 7,294,5997,601,665, 7,884,163, 8,114,946, and 8,309,485.

Unsaturated monomers that can be employed with the titanatedchromium/silica catalysts and polymerization processes of this inventiontypically can include olefin compounds having from 2 to 30 carbon atomsper molecule and having at least one olefinic double bond. Thisinvention encompasses homopolymerization processes using a single olefinsuch as ethylene or propylene, as well as copolymerization,terpolymerization, etc., reactions using an olefin monomer with at leastone different olefinic compound. For example, the resultant ethylenecopolymers, terpolymers, etc., generally can contain a major amount ofethylene (>50 mole percent) and a minor amount of comonomer (<50 molepercent), though this is not a requirement. Comonomers that can becopolymerized with ethylene often can have from 3 to 20 carbon atoms, orfrom 3 to 10 carbon atoms, in their molecular chain.

Acyclic, cyclic, polycyclic, terminal (a), internal, linear, branched,substituted, unsubstituted, functionalized, and non-functionalizedolefins can be employed in this invention. For example, typicalunsaturated compounds that can be polymerized with the titanatedchromium/silica catalysts of this invention can include, but are notlimited to, ethylene, propylene, 1-butene, 2-butene, 3-methyl-1-butene,isobutylene, 1-pentene, 2-pentene, 3-methyl-1-pentene,4-methyl-1-pentene, 1-hexene, 2-hexene, 3-hexene, 3-ethyl-1-hexene,1-heptene, 2-heptene, 3-heptene, the four normal octenes (e.g.,1-octene), the four normal nonenes, the five normal decenes, and thelike, or mixtures of two or more of these compounds. Cyclic and bicyclicolefins, including but not limited to, cyclopentene, cyclohexene,norbornylene, norbornadiene, and the like, also can be polymerized asdescribed herein. Styrene can also be employed as a monomer in thepresent invention. In an aspect, the olefin monomer can comprise aC₂-C₂₀ olefin; alternatively, a C₂-C₂₀ alpha-olefin; alternatively, aC₂-C₁₀ olefin; alternatively, a C₂-C₁₀ alpha-olefin; alternatively, theolefin monomer can comprise ethylene; or alternatively, the olefinmonomer can comprise propylene.

When a copolymer (or alternatively, a terpolymer) is desired, the olefinmonomer and the olefin comonomer independently can comprise, forexample, a C₂-C₂₀ alpha-olefin. In some aspects, the olefin monomer cancomprise ethylene or propylene, which is copolymerized with at least onecomonomer (e.g., a C₂-C₂₀ alpha-olefin, a C₃-C₂₀ alpha-olefin, etc.).According to one aspect of this invention, the olefin monomer used inthe polymerization process can comprise ethylene. In this aspect,examples of suitable olefin comonomers can include, but are not limitedto, propylene, 1-butene, 2-butene, 3-methyl-1-butene, isobutylene,1-pentene, 2-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene,2-hexene, 3-ethyl-1-hexene, 1-heptene, 2-heptene, 3-heptene, 1-octene,1-decene, styrene, and the like, or combinations thereof. According toanother aspect of the present invention, the olefin monomer can compriseethylene, and the comonomer can comprise a C₃-C₁₀ alpha-olefin;alternatively, the comonomer can comprise 1-butene, 1-pentene, 1-hexene,1-octene, 1-decene, styrene, or any combination thereof; alternatively,the comonomer can comprise 1-butene, 1-hexene, 1-octene, or anycombination thereof, alternatively, the comonomer can comprise 1-butene;alternatively, the comonomer can comprise 1-hexene; or alternatively,the comonomer can comprise 1-octene.

Generally, the amount of comonomer introduced into a polymerizationreactor system to produce a copolymer can be from 0.01 to 50 weightpercent, based on the total weight of the monomer and comonomer.According to another aspect of the present invention, the amount ofcomonomer introduced into a polymerization reactor system can be from0.01 to 40 weight percent comonomer, based on the total weight of themonomer and comonomer, or alternatively, from 0.1 to 35 weight percentcomonomer, or from 0.5 to 20 weight percent comonomer.

While not intending to be bound by this theory, where branched,substituted, or functionalized olefins are used as reactants, it isbelieved that a steric hindrance can impede and/or slow thepolymerization process. Thus, branched and/or cyclic portion(s) of theolefin removed somewhat from the carbon-carbon double bond would not beexpected to hinder the reaction in the way that the same olefinsubstituents situated more proximate to the carbon-carbon double bondmight.

According to one aspect of the present invention, at least onemonomer/reactant can be ethylene (or propylene), so the polymerizationreaction can be a homopolymerization involving only ethylene (orpropylene), or a copolymerization with a different acyclic, cyclic,terminal, internal, linear, branched, substituted, or unsubstitutedolefin. In addition, the titanated chromium/silica catalysts of thisinvention can be used in the polymerization of diolefin compoundsincluding, but not limited to, 1,3-butadiene, isoprene, 1,4-pentadiene,and 1,5-hexadiene.

The titanated chromium/silica catalysts of the present invention areintended for any olefin polymerization method using various types ofpolymerization reactor systems and reactors. The polymerization reactorsystem can include any polymerization reactor capable of polymerizingolefin monomers and comonomers (one or more than one comonomer) toproduce homopolymers, copolymers, terpolymers, and the like. The varioustypes of reactors include those that can be referred to as a batchreactor, slurry reactor, gas-phase reactor, solution reactor, highpressure reactor, tubular reactor, autoclave reactor, and the like, orcombinations thereof. The polymerization conditions for the variousreactor types are well known to those of skill in the art. Gas phasereactors can comprise fluidized bed reactors or staged horizontalreactors. Slurry reactors can comprise vertical or horizontal loops.High pressure reactors can comprise autoclave or tubular reactors. Thesereactor types generally can be operated continuously. Continuousprocesses can use intermittent or continuous polymer product discharge.Polymerization reactor systems and processes also can include partial orfull direct recycle of unreacted monomer, unreacted comonomer, and/ordiluent.

Polymerization reactor systems of the present invention can comprise onetype of reactor in a system or multiple reactors of the same ordifferent type (e.g., a single reactor, dual reactor, more than tworeactors). For instance, the polymerization reactor system can comprisea solution reactor, a gas-phase reactor, a slurry reactor, or acombination of two or more of these reactors. Production of polymers inmultiple reactors can include several stages in at least two separatepolymerization reactors interconnected by a transfer device making itpossible to transfer the polymer resulting from the first polymerizationreactor into the second reactor. The polymerization conditions in one ofthe reactors can be different from the operating conditions of the otherreactor(s). Alternatively, polymerization in multiple reactors caninclude the manual transfer of polymer from one reactor to subsequentreactors for continued polymerization. Multiple reactor systems caninclude any combination including, but not limited to, multiple loopreactors, multiple gas phase reactors, a combination of loop and gasphase reactors, multiple high pressure reactors, or a combination ofhigh pressure with loop and/or gas phase reactors. The multiple reactorscan be operated in series, in parallel, or both. Accordingly, thepresent invention encompasses polymerization reactor systems comprisinga single reactor, comprising two reactors, and comprising more than tworeactors. The polymerization reactor system can comprise a slurryreactor, a gas-phase reactor, a solution reactor, in certain aspects ofthis invention, as well as multi-reactor combinations thereof.

According to one aspect, the polymerization reactor system can compriseat least one loop slurry reactor, e.g., comprising vertical orhorizontal loops. Monomer, diluent, catalyst, and optional comonomer canbe continuously fed to a loop reactor where polymerization occurs.Generally, continuous processes can comprise the continuous introductionof monomer/comonomer, a catalyst, and a diluent into a polymerizationreactor and the continuous removal from this reactor of a suspensioncomprising polymer particles and the diluent. Reactor effluent can beflashed to remove the solid polymer from the liquids that comprise thediluent, monomer and/or comonomer. Various technologies can be used forthis separation step including, but not limited to, flashing that caninclude any combination of heat addition and pressure reduction,separation by cyclonic action in either a cyclone or hydrocyclone, orseparation by centrifugation.

A typical slurry polymerization process (also known as the particle formprocess) is disclosed, for example, in U.S. Pat. Nos. 3,248,179,4,501,885, 5,565,175, 5,575,979, 6,239,235, 6,262,191, 6,833,415, and8,822,608. Suitable diluents used in slurry polymerization include, butare not limited to, the monomer being polymerized and hydrocarbons thatare liquids under reaction conditions. Examples of suitable diluentsinclude, but are not limited to, hydrocarbons such as propane,cyclohexane, isobutane, n-butane, n-pentane, isopentane, neopentane, andn-hexane. Some loop polymerization reactions can occur under bulkconditions where no diluent is used, such as can be employed in the bulkpolymerization of propylene to form polypropylene homopolymers.

According to yet another aspect, the polymerization reactor system cancomprise at least one gas phase reactor (e.g., a fluidized bed reactor).Such reactor systems can employ a continuous recycle stream containingone or more monomers continuously cycled through a fluidized bed in thepresence of the catalyst under polymerization conditions. A recyclestream can be withdrawn from the fluidized bed and recycled back intothe reactor. Simultaneously, polymer product can be withdrawn from thereactor and new or fresh monomer can be added to replace the polymerizedmonomer. Such gas phase reactors can comprise a process for multi-stepgas-phase polymerization of olefins, in which olefins are polymerized inthe gaseous phase in at least two independent gas-phase polymerizationzones while feeding a catalyst-containing polymer formed in a firstpolymerization zone to a second polymerization zone. One type of gasphase reactor is disclosed in U.S. Pat. Nos. 5,352,749, 4,588,790,5,436,304, 7,531,606, and 7,598,327.

According to still another aspect, the polymerization reactor system cancomprise a high pressure polymerization reactor, e.g., can comprise atubular reactor or an autoclave reactor. Tubular reactors can haveseveral zones where fresh monomer, initiators, or titanatedchromium/silica catalysts are added. Monomer can be entrained in aninert gaseous stream and introduced at one zone of the reactor.Initiators, titanated chromium/silica catalysts, and/or catalystcomponents can be entrained in a gaseous stream and introduced atanother zone of the reactor. The gas streams can be intermixed forpolymerization. Heat and pressure can be employed appropriately in suchhigh pressure polymerization reactors to obtain optimal polymerizationreaction conditions.

According to yet another aspect, the polymerization reactor system cancomprise a solution polymerization reactor, wherein themonomer/comonomer can be contacted with the catalyst by suitablestirring or other means. A carrier comprising an inert organic diluentor excess monomer can be employed. If desired, the monomer/comonomer canbe brought in the vapor phase into contact with the catalytic reactionproduct, in the presence or absence of liquid material. Thepolymerization zone can be maintained at temperatures (e.g., up tobetween 150° C. and 180° C.) and pressures that will result in theformation of a solution of the polymer in a reaction medium. Agitationcan be employed to obtain better temperature control and to maintainuniform polymerization mixtures throughout the polymerization zone.Adequate means are utilized for dissipating the exothermic heat ofpolymerization.

In some aspects, the polymerization reactor system can comprise anycombination of a raw material feed system, a feed system for catalystand/or catalyst components, and/or a polymer recovery system, includingcontinuous systems. In other aspects, suitable reactor systems cancomprise systems for feedstock purification, catalyst storage andpreparation, extrusion, reactor cooling, polymer recovery,fractionation, recycle, storage, loadout, laboratory analysis, andprocess control.

Polymerization conditions that can be monitored, adjusted, and/orcontrolled for efficiency and to provide desired polymer properties caninclude, but are not limited to, reactor temperature, reactor pressure,catalyst system flow rate into the reactor, monomer flow rate (andcomonomer, if employed) into the reactor, monomer concentration in thereactor, olefin polymer output rate, recycle rate, hydrogen flow rate(if employed), reactor cooling status, and the like. Polymerizationtemperature can affect catalyst productivity, polymer molecular weight,and molecular weight distribution. A suitable polymerization temperaturecan be any temperature below the de-polymerization temperature accordingto the Gibbs Free energy equation. Typically, this includes from 60° C.to 280° C., for example, from 60° C. to 185° C., from 60° C. to 120° C.,or from 130° C. to 180° C., depending upon the type of polymerizationreactor, the polymer grade, and so forth. In some reactor systems, thepolymerization reactor temperature generally can be within a range from70° C. to 110° C., or from 125° C. to 175° C. Various polymerizationconditions can be held substantially constant, for example, for theproduction of a particular grade of olefin polymer.

Suitable pressures will also vary according to the reactor andpolymerization type. The pressure for liquid phase polymerizations in aloop reactor typically can be less than 1000 psig (6.9 MPa). Thepressure for gas phase polymerization usually can be in the 200 psig to500 psig range (1.4 MPa to 3.4 MPa). High pressure polymerization intubular or autoclave reactors generally can be conducted at 20,000 psigto 75,000 psig (138 MPa to 517 MPa). Polymerization reactors can also beoperated in a supercritical region occurring at generally highertemperatures and pressures (for instance, above 92° C. and 700 psig(4.83 MPa)). Operation above the critical point of apressure/temperature diagram (supercritical phase) can offer advantagesto the polymerization reaction process.

Aspects of this invention also are directed to olefin polymerizationprocesses conducted in the absence of added hydrogen. An olefinpolymerization process of this invention can comprise contacting atitanated chromium/silica catalyst and an optional co-catalyst with anolefin monomer and optionally an olefin comonomer in a polymerizationreactor system under polymerization conditions to produce an olefinpolymer, and wherein the polymerization process is conducted in theabsence of added hydrogen (no hydrogen is added to the polymerizationreactor system). As one of ordinary skill in the art would recognize,hydrogen can be generated in-situ by certain catalyst systems in variousolefin polymerization processes, and the amount generated can varydepending upon the specific catalyst components employed, the type ofpolymerization process used, the polymerization reaction conditionsutilized, and so forth.

In other aspects, it may be desirable to conduct the polymerizationprocess in the presence of a certain amount of added hydrogen.Accordingly, an olefin polymerization process of this invention cancomprise contacting a titanated chromium/silica catalyst and an optionalco-catalyst with an olefin monomer and optionally an olefin comonomer ina polymerization reactor system under polymerization conditions toproduce an olefin polymer, wherein the polymerization process isconducted in the presence of added hydrogen (hydrogen is added to thepolymerization reactor system). For example, the ratio of hydrogen tothe olefin monomer in the polymerization process can be controlled,often by the feed ratio of hydrogen to the olefin monomer entering thereactor. The amount of hydrogen added (based on the amount of olefinmonomer) to the process can be controlled at a molar percentage whichgenerally falls within a range from 0.05 to 20 mole %, from 0.1 to 15mole %, from 0.25 to 10 mole %, or from 0.5 to 10 mole %. In someaspects of this invention, the feed or reactant ratio of hydrogen toolefin monomer can be maintained substantially constant during thepolymerization run for a particular polymer grade. That is, thehydrogen:olefin monomer ratio can be selected at a particular ratio, andmaintained at the ratio to within +/−25% during the polymerization run.Further, the addition of comonomer (or comonomers) can be, and generallyis, substantially constant throughout the polymerization run for aparticular polymer grade. However, in other aspects, it is contemplatedthat monomer, comonomer (or comonomers), and/or hydrogen can beperiodically pulsed to the reactor, for instance, in a manner similar tothat employed in U.S. Pat. No. 5,739,220 and U.S. Patent Publication No.2004/0059070.

The concentration of the reactants entering the polymerization reactorsystem can be controlled to produce resins with certain physical andmechanical properties. The proposed end-use product that will be formedby the polymer resin and the method of forming that product ultimatelycan determine the desired polymer properties and attributes. Mechanicalproperties include tensile, flexural, impact, creep, stress relaxation,and hardness tests. Physical properties include density, molecularweight, molecular weight distribution, melting temperature, glasstransition temperature, temperature melt of crystallization, density,stereoregularity, crack growth, long chain branching, and rheologicalmeasurements. This invention is also directed to, and encompasses, thepolymers produced by any of the polymerization processes disclosedherein. Articles of manufacture can be formed from, and/or can comprise,the polymers produced in accordance with this invention.

Polymers and Articles

Olefin polymers encompassed herein can include any polymer produced fromany olefin monomer and optional comonomer(s) described herein. Forexample, the olefin polymer can comprise an ethylene homopolymer, anethylene copolymer (e.g., ethylene/α-olefin, ethylene/1-butene,ethylene/1-hexene, ethylene/1-octene, etc.), a propylene homopolymer, apropylene copolymer, an ethylene terpolymer, a propylene terpolymer, andthe like, including any combinations thereof. In one aspect, the olefinpolymer can comprise an ethylene homopolymer, while in another aspect,the olefin polymer can comprise an ethylene/1-butene copolymer, anethylene/1-hexene copolymer, and/or an ethylene/1-octene copolymer,while in yet another aspect, the olefin polymer can comprise anethylene/1-hexene copolymer.

If the resultant polymer produced in accordance with the presentinvention is, for example, an ethylene polymer, its properties can becharacterized by various analytical techniques known and used in thepolyolefin industry. Articles of manufacture can be formed from, and/orcan comprise, the olefin polymers (e.g., ethylene polymers) of thisinvention, whose typical properties are provided below.

Ethylene polymers produced in accordance with this invention can have amelt index (MI) of less than or equal to 100 g/10 min. Suitable rangesfor the MI can include, but are not limited to, from 0.1 to 10, from 0.2to 5, or from 0.25 to 2 g/10 min, and the like. Additionally oralternatively, the ethylene polymers can have a high load melt index(HLMI) of from 1 to 1000, from 5 to 500, from 6 to 40, from 8 to 60,from 10 to 100, or from 12 to 50 g/10 min, and the like.

The densities of ethylene-based polymers produced using the titanatedchromium/silica catalysts and the processes disclosed herein often aregreater than or equal to 0.91 g/cm³. In one aspect of this invention,the density of the ethylene polymer can be in a range from 0.92 to 0.965g/cm³. Yet, in another aspect, the density can be in a range from 0.93to 0.96 g/cm³, such as, for example, from 0.935 to 0.955 g/cm³, or from0.94 to 0.95 g/cm³.

In an aspect, ethylene polymers described herein can have a ratio ofMw/Mn, or the polydispersity index, of greater than or equal to 5,greater than or equal to 7, or greater than or equal to 9. Often, theMw/Mn can range up to 15-30, therefore, non-limiting ranges for Mw/Mninclude from 5 to 30, from 7 to 25, from 9 to 20, from 10 to 25, or from10 to 15, and the like. Additionally or alternatively, the ethylenepolymer can have a Mw in a range from 10 to 500 kg/mol, and more often,from 30 to 300, from 50 to 400, from 50 to 250, from 80 to 200, or from100 to 250 kg/mol. Additionally or alternatively, the ethylene polymercan have a Mn in a range from 1 to 50 kg/mol, and more often, from 3 to30, from 4 to 40, from 5 to 25, or from 8 to 20 kg/mol.

The Carreau-Yasuda “a” parameter (CY-a parameter) is particularlysensitive to small changes in LCB. In an aspect, ethylene polymersdescribed herein can have a CY-a parameter in a range from 0.05 to 0.5,from 0.08 to 0.4, or from 0.1 to 0.3, while in another aspect, theethylene polymers described herein can have a CY-a parameter in a rangefrom 0.1 to 0.25 or from 0.15 to 0.25.

Polymers of ethylene, whether homopolymers, copolymers, and so forth,can be formed into various articles of manufacture. Articles which cancomprise polymers of this invention include, but are not limited to, anagricultural film, an automobile part, a bottle, a drum, a fiber orfabric, a food packaging film or container, a food service article, afuel tank, a geomembrane, a household container, a liner, a moldedproduct, a medical device or material, a pipe, a sheet or tape, a toy,and the like. Various processes can be employed to form these articles.Non-limiting examples of these processes include injection molding, blowmolding, rotational molding, film extrusion, sheet extrusion, profileextrusion, thermoforming, and the like. Additionally, additives andmodifiers are often added to these polymers in order to providebeneficial polymer processing or end-use product attributes. Suchprocesses and materials are described in Modern Plastics Encyclopedia,Mid-November 1995 Issue, Vol. 72, No. 12; and Film ExtrusionManual—Process, Materials, Properties, TAPPI Press, 1992.

Processes for Producing Titanated Silica Supports

Aspects of this invention are directed to processes for preparing atitanated silica support. A first process can comprise (or consistessentially of, or consist of) (i) contacting water, a peroxidecompound, and a titanium precursor to form a first mixture, (ii)contacting a silica with the first mixture under conditions sufficientfor titanium to adsorb onto the silica and form a second mixture, (iii)isolating a solid fraction from the second mixture, and (iv) drying thesolid fraction to form the titanated silica support. A second processcan comprise (or consist essentially of, or consist of) (a) contactingwater, hydrogen peroxide, an alkali metal precursor and/or a zincprecursor, a nitrogen-containing compound, and a titanium precursor toform a first mixture, (b) contacting a silica with the first mixtureunder conditions sufficient for titanium to adsorb onto the silica andform a second mixture, (c) subjecting the second mixture to a reactiontemperature in a range from 40 to 100° C., (d) isolating a solidfraction from the second mixture and washing the solid fraction, and (e)drying the solid fraction to form the titanated silica support. A thirdprocess can comprise (or consist essentially of, or consist of) (A)contacting water, hydrogen peroxide, an alkali metal precursor and/or azinc precursor, and a titanium precursor to form a first mixture, (B)contacting a silica with the first mixture under conditions sufficientfor titanium to adsorb onto the silica and form a second mixture, (C)subjecting the second mixture to a reaction temperature in a range from40 to 100° C., (D) isolating a solid fraction from the second mixtureand washing the solid fraction, and (E) drying the solid fraction toform the titanated silica support. In the second and third processes,the alkali metal precursor (or zinc precursor) is any suitable source ofalkali metal (or zinc) or any compound that generates an alkali metal(or zinc) in water. The third process has very low emissions, sincenitrogen compounds and organics (hydrocarbons) are not required.

Generally, the features of these processes (e.g., the relative amountsof the water, peroxides, alkali metal or zinc precursors, and titaniumprecursor; the alkali metal precursor; the titanium precursor; the pH;the characteristics of the silica; the reaction temperature; theisolating and washing techniques; and the features of the drying step,among others) are independently described herein and these features canbe combined in any combination to further describe the disclosedprocesses to produce a titanated silica support. Moreover, additionalprocess steps can be performed before, during, and/or after any of thesteps in any of the processes disclosed herein, and can be utilizedwithout limitation and in any combination to further describe theseprocesses, unless stated otherwise. Further, any titanated silicasupports produced in accordance with the disclosed processes are withinthe scope of this disclosure and are encompassed herein.

The specific peroxide compound used herein is not particularly limitedand may be any peroxide compound suitable for providing effectivetitanation of the olefin polymerization catalyst and the pre-catalystthereof. In an aspect, the peroxide compound comprises organicperoxides, diacyl peroxides, peroxydicarbonates, monoperoxycarbonates,peroxyketals, peroxyesters, dialkyl peroxides, hydroperoxides, peracids,or any combination thereof. In another aspect, the peroxide compoundcomprises hydrogen peroxide, di-tert-butyl peroxide, benzoyl peroxide,dicumyl peroxide, cumene hydroperoxide, tert-butyl hydroperoxide,phthaloyl peroxide, or any combination thereof. In yet another aspect,the peroxide compound comprises (or consists essentially or, or consistsof) hydrogen peroxide.

In the first step of the first process, the second process, and thethird process, the materials can be contacted or combined in any orderof sequence to form the first mixture. For instance, the water andperoxide compound or hydrogen peroxide can be contacted first, followedby the alkali metal precursor (if used) and then the titanium precursorto form the first mixture, while in another aspect, the water and alkalimetal precursor (if used) can be contacted first, followed by theperoxide and then the titanium precursor to form the first mixture. Thisstep to form the first mixture can be performed at any suitabletemperature (e.g., room temperature) and for any suitable period oftime.

The first step of each of these processes can alternatively be describedas forming a first mixture. Thus, step (i) of the first process can bedescribed as forming a first mixture comprising (or consistingessentially of, or consisting of) water, a peroxide compound, and atitanium precursor, while step (a) of the second process can bedescribed as forming a first mixture comprising (or consistingessentially of, or consisting of) water, hydrogen peroxide, an alkalimetal precursor and/or a zinc precursor, a nitrogen-containing compound,and a titanium precursor, and step (A) of the third process can bedescribed as forming a first mixture comprising (or consistingessentially of, or consisting of) water, hydrogen peroxide, an alkalimetal precursor and/or a zinc precursor, and a titanium precursor.

The relative amounts of the components in the first step are notparticularly limited, so long as any component or reaction product doesnot adversely affect the porosity of the silica support and supportedchromium catalyst in subsequent processing steps, discussed hereinbelow.Generally, the molar ratio of the peroxide compound or hydrogen peroxideto titanium (e.g., H₂O₂:Ti) in first step can fall within a range from0.5:1 to 100:1, such as from 2:1 to 50:1, from 3:1 to 20:1, or from 5:1to 11:1, and the like. Additionally or alternatively, the molar ratio ofthe alkali metal (or zinc) to titanium in the first step of the secondprocess and the third process can fall within a range from 0.1:1 to300:1, such as from 0.2:1 to 100:1, from 0.5:1 to 20:1, from 0.7:1 to10:1, from 1:1 to 5:1, or from 1:1 to 3:1, and the like. Note thatexcess zinc or alkali metal, such as sodium, can be used during thefirst step, but can be subsequently washed out during a later step inthe respective process. Additionally or alternatively, the weight ratioof titanium to water (Ti:H₂O) the first step of the first, second, andthird processes can range from 0.0001:1 to 0.02:1 in one aspect, from0.001:1 to 0.02:1 in another aspect, from 0.005:1 to 0.02:1 in yetanother aspect, and from 0.03:1 to 0.07:1 in still another aspect.

The specific titanium source or precursor used in first step is notparticularly limited. Consistent with certain aspects of this invention,the titanium precursor can comprise a Ti (III) compound and/or a Ti (IV)compound. Representative and non-limiting examples of suitable titaniumprecursors can include a titanium carboxylate (e.g., titanium oxalate,titanium glycolate, titanium lactate, titanium citrate, titaniummalate), a titanium halide, a titanium oxide, a titanium hydroxide, atitanium alkoxide (e.g., titanium isopropoxide, titanium n-propoxide), atitanium sulfate, a titanium nitrate, a titanium oxy-compound (such asthe oxysulfate (TiOSO₄), or the oxynitrate (TiO(NO₃)₂, or theoxychloride (TiOCl₂), etc.) and the like. Mixtures or combinations ortwo or more titanium compounds can be used as the titanium precursor. Insome aspects contemplated herein, the titanium precursor can compriseTiOSO₄, Ti(OH)₄, Ti metal, Ti(OR)₄, TiO(OH)₂, TiO₂, and the like, aswell as any mixture or combination thereof, while in other aspects, thetitanium precursor can comprise TiOSO₄; alternatively, Ti(OH)₄;alternatively, Ti metal; alternatively, Ti(OR)₄; alternatively, a Tiacetylacetonate or derivative thereof; alternatively, TiO(OH)₂; oralternatively, TiO₂.

If a nitrogen-containing compound is used in the first step (e.g., thesecond process), illustrative and non-limiting examples include ammonia,ammonium hydroxide, an alkyl-substituted ammonium hydroxide, ammoniumsalts, amines, alkanolamines, and the like, and mixtures of two or moresuitable nitrogen-containing materials can be utilized, if desired. Therelative amount of the nitrogen-containing compound is not particularlylimited, so long as a desirable pH is reached. However, typical weightratios of the nitrogen-containing compound (e.g., NH₃) to titaniuminclude from 5:1 to 300:1, from 10:1 to 200:1, from 25:1 to 150:1, orfrom 50:1 to 100:1, and so forth.

Often, the pH of the first mixture in the first step is balanced by therelative amounts of the titanium precursor and H₂O₂ (acid) versus thenitrogen-containing compound and the alkali metal precursor (base).Nonetheless, prior to contacting a silica with the first mixture in thesecond step, optionally these processes can further comprise a step ofadjusting a pH of the first mixture to within a range of from 3 to 12.More often, the pH is adjusted to within a range from 3 to 10, from 4 to12, from 4 to 10, or from 6 to 10, and the like.

A suitable silica is contacted with the first mixture in the secondstep. In one aspect, the silica is a pre-formed xerogel silica and canhave any of the pore volume, surface area, and average particle sizefeatures disclosed hereinabove for the titanated silica supports and thetitanated chromium/silica-pre-catalysts, such as a pore volume from 0.5to 3 mL/g, a BET surface area from 100 to 700 m²/g, and an average (d50)particle size from 15 to 350 μm. The preformed silica used in the secondstep is not a colloid or sol, and typically contains less than or equalto 25 wt. %, water/moisture, and more often, less than or equal to 20wt. %, less than or equal to 15 wt. %, or less than or equal to 10 wt. %water/moisture, based on the total weight of the silica. The preformedsilica is typically in powder or bead form.

In another aspect, the silica contacted with the first mixture is asilica hydrogel, colloid, or sol, and in such instances, can contain atleast 50 wt. % water, and in some aspects, at least 60 wt. %, at least70 wt. %, or at least 80 wt. % water.

Any reasonable amount of the silica can be added to the first mixture inthe second step to from the second mixture. In one aspect, for instance,the weight ratio of silica to water (silica:H₂O) can fall within a rangefrom 0.001:1 to 1:1, while in another aspect, the weight ratio can rangefrom 0.01:1 to 0.5:1, and in yet another aspect, the weight ratio canrange from 0.05:1 to 0.4:1, and in still another aspect, the weightratio can range from 0.1:1 to 0.3:1.

As discussed herein, and unlike other aqueous based catalyst preparationprocedures, the titanium is adsorbed onto the silica in the second stepof the first, second, and third processes. The adsorbed titanium isgenerally accompanied by a color change of the silica support—typically,initially white and changing to yellow upon adsorption of the Ti peroxocomplex—that does not wash off the support in subsequent steps. It isbelieved that the yellow color is the result of adsorption of a peroxycomplex of titanium, and the color changes observed during catalystpreparation are described in the examples that follow. Analysis oftitanium on the silica and in the solution before and after adsorptiondemonstrate that the titanium is definitely adsorbed, usuallyquantitatively, onto the silica as part of the catalyst preparation.When the Ti is not adsorbed, such as when the contact time isinsufficient, then the MI potential of the final catalyst is usuallylow, indicating that the Ti did not attach to the silica surface in thedesired way. If adsorption does not happen, the Ti can also be washedout later in subsequent steps.

This step to form the second mixture in which the titanium is adsorbedonto the silica can be conducted under any conditions suitable for thetitanium to absorb onto the silica (e.g., accompanying color change tothe silica). Any suitable temperature (e.g., room temperature) and timecan be used for this step, and at any suitable pH. The titaniumadsorption can be determined by slurrying the solid fraction isolatedfrom the second mixture (discussed further below) in water, filteringthe slurry, often leaving yellow solids on the filter, and a clearsolution (filtrate) passing thru the filter. Spectroscopic analysis ofthe silica solids before and after this step can be used to measure thecolor change. The filtrate solution then can be acidified by adding 3 mLof concentrated H₂SO₄, bringing the pH to about 1, and adding 5 mL of30% H₂O₂. This combination (acid and H₂O₂) results in a deep orangecolor if titanium is present in the filtrate. If no color change isobserved, then the titanium has been adsorbed onto the silica.Spectroscopic analysis also can be used to measure the color change inthe filtrate, if any.

The first and second steps in the first, second, and third processesgenerally use an aqueous medium, where substantially no hydrocarbons oralcohol solvents are present. For instance, the first mixture and thesecond mixture can contain less than or equal to 20 wt. % hydrocarbonsand alcohols, such as less than or equal to 10 wt. %, less than or equalto 5 wt. %, less than or equal to 2 wt. %, or less than or equal to 1wt. % hydrocarbons and alcohols.

Although not required, the second mixture containing the silica supportis subjected to a reaction temperature in a range from 40 to 100° C. inthe third step—step (c) and step (C)—of the second and third processes.Other representative and non-limiting ranges for the reactiontemperature can include from 50° C. to 100° C., from 60° C. to 100° C.,from 70° C. to 100° C., or from 80° C. to 100° C. These temperatureranges also are meant to encompass circumstances where this step isperformed at a series of different temperatures, instead of at a singlefixed temperature, falling within the respective temperature ranges,wherein at least one temperature falls within the respective ranges. Ifthe second step is performed at room temperature, then the resultingsecond mixture is heated to the desired reaction temperature. In someaspects, the reaction temperature can be controlled by heating to theboiling point of the solvent, e.g., refluxing.

The time period for which the second mixture is subjected to thereaction temperature is not particularly limited, and can be performedfor any suitable period of time. In some aspects, the time period canrange from 10 min to 4 days or from 20 min to 2 days. In other aspects,the time period can range from 30 min to 24 hr or from 40 min to 2 hr.

In step (iii), step (d), and step (D) of the respective first process,second process, and third process, a solid fraction is isolated from thesecond mixture, and optionally the solid fraction is washed. Referringfirst to isolating the solid fraction (e.g., removing water), anysuitable technique can be used, and illustrative examples includefiltering, settling, decanting, pressing, centrifuging, cycloning,hydrocycloning, and the like. Two or more of these techniques can beused, and the isolating step can be performed batchwise or continuously,and at any suitable temperature (e.g., from 25° C. to 100° C.).

If washed, the solid fraction is washed one or more times with anysuitable wash solution. While not limited thereto, the wash solution cancontain water, an alcohol (e.g., ethanol), or a mixture thereof. As anexample, the solid fraction can be washed one or more times with waterand one or more times with an alcohol, and in any order or sequence.Similar to the isolating step, washing can be performed batchwise orcontinuously, and at any suitable temperature (e.g., from 25° C. to 100°C.). Other organic solvents also can be used, such as ketones orglycols, for washing either alone or in mixtures with water or othersolvents. The washing step may include one or more steps where the solidfraction is redispersed in a solution. The redispersing solution cancontain the filtrate, water, an alcohol (e.g., ethanol), or a mixturethereof. This solution also can contain a dilute acid, such as anysuitable acid, e.g., nitric acid or acetic acid. While not wishing to bebound by theory, it is believed that the washing step removes looselybound surface titanium and alkali metal species (if present). However,it is believed that even after washing, some of the sodium remainsadsorbed to the inventive supports (or inventive pre-catalysts) and doesnot wash away. The relatively high amount of sodium present isunexpected, since sodium at these high levels is normally a catalystpoison.

Drying the solid fraction to form the titanated silica support canencompass a wide range of drying times, drying temperatures, and dryingpressures, depending upon the drying device or technique that isutilized. For example, the drying time can range from 1 sec to 1 day,from 1 hr to 12 hr, from 2 hr to 8 hr, or from 0.1 to 5 sec, and thedrying temperature can range from 25° C. to 200° C., from 50° C. to 150°C., from 70° C. to 120° C., or from 90° C. to 110° C. The dryingpressure can be at or around atmospheric pressure, but in manyinstances, the drying step can be conducted under vacuum conditions atany suitable sub-atmospheric pressure, such as less than 100 torr (13.3kPa), less than 50 (6.67 kPa) torr, or less than 10 torr (1.33 kPa).

Various types of drying techniques can be used for the drying step, suchas spray drying, tray drying, flash drying, freeze drying, oven drying,or microwave drying, although not limited thereto. In one aspect, thedrying step comprises spray drying, while in another aspect, the dryingstep comprises flash drying.

Processes for Producing Titanated Chromium Silica Catalysts

Aspects of this invention also are directed to processes for preparingtitanated chromium/silica pre-catalysts and titanated chromium/silicacatalysts. One such process for preparing a titanated chromium/silicapre-catalyst can comprise performing any of the processes to prepare atitanated silica support disclosed hereinabove (e.g., the first process,the second process, or the third process), and contacting a chromiumprecursor with the first mixture or the second mixture in any step priorto the step of isolating the solid fraction from the second mixture.Another process for preparing a titanated chromium/silica pre-catalystcan comprise performing any of the processes to prepare a titanatedsilica support disclosed hereinabove, and contacting a chromiumprecursor with the solid fraction after isolating the solid fractionfrom the second mixture (and this can be accomplished before or afterdrying the solid fraction). For instance, after drying to form thetitanated silica support (dried), the chromium precursor can becontacted (e.g., wet or dry mix) with the titanated silica support, andoptionally dried if needed. In yet another process, a chromium/silicapre-catalyst (pre-formed) is used instead of silica, and in the aspect,the process to prepare the titanated chromium/silica pre-catalyst cancomprise performing any of the processes to prepare a titanated silicasupport disclosed hereinabove (e.g., the first process, the secondprocess, or the third process), but instead of contacting the silicawith the first mixture, contacting a chromium/silica pre-catalyst withthe first mixture. Thus, rewording the first process for preparing atitanated silica support into a process for preparing a titanatedchromium/silica pre-catalyst would comprise the following steps: (i)contacting water, a peroxide compound, and a titanium precursor to forma first mixture, (ii) contacting a chromium/silica pre-catalyst with thefirst mixture under conditions sufficient for titanium to adsorb ontothe silica and form a second mixture, (iii) isolating a solid fractionfrom the second mixture, and (iv) drying the solid fraction to form thetitanated chromium/silica pre-catalyst. Titanated chromium/silicapre-catalysts produced in accordance with any of these processes arewithin the scope of this disclosure and are encompassed herein.

Any suitable chromium source or chromium precursor can be used to formthe titanated chromium/silica pre-catalyst. Consistent with certainaspects of this invention, the chromium precursor can comprise achromium (II) compound, a chromium (III) compound, or any combinationthereof. Illustrative and non-limiting examples of chromium (II)compounds can include chromium (II) acetate, chromium (II) chloride,chromium (II) bromide, chromium (II) iodide, chromium (II) sulfate, andthe like, as well as combinations thereof. Likewise, illustrative andnon-limiting examples of chromium (III) compounds can include a chromium(III) carboxylate, a chromium (III) naphthenate, a chromium (III)halide, chromium (III) sulfate, chromium (III) nitrate, a chromium (III)dionate, and the like, as well as combinations thereof. In some aspects,the chromium precursor can comprise chromium (III) acetate, chromium(III) acetylacetonate, chromium (III) chloride, chromium (III) bromide,chromium (III) sulfate, chromium (III) nitrate, and the like, as well ascombinations thereof.

In one aspect, the chromium precursor can comprise chromium trioxide,chromium acetate, chromium hydroxy acetate, chromium nitrate, or anycombination thereof, while in another aspect, the chromium precursor cancomprise chromium trioxide; alternatively, chromium acetate;alternatively, chromium hydroxy acetate; or alternatively, chromiumnitrate.

While not required, it can be beneficial for the chromium precursor tobe soluble in a suitable solvent, such as an alcohol, depending uponwhich step of the process is the chromium incorporation step. Similarly,and also not required, it can be beneficial for the chromium precursorcompound to be soluble in water, and again, depending upon which step ofthe process is the chromium incorporation step.

The resulting titanated chromium/silica pre-catalysts can be convertedto titanated chromium/silica catalysts via an appropriate activationstep (often referred to as a calcining step). Thus, a representativeprocess for preparing a titanated chromium/silica catalyst can compriseperforming any process for preparing a titanated chromium/silicapre-catalyst disclosed hereinabove, and activating the titanatedchromium/silica pre-catalyst to form the (activated) titanatedchromium/silica catalyst. Further, any titanated chromium/silicacatalysts produced in accordance with these processes are within thescope of this disclosure and are encompassed herein.

The activating step can be conducted at a variety of temperatures andtime periods, which are generally selected to convert all or a largeportion of the chromium to hexavalent chromium. Typical peak activationtemperatures include the following representative ranges: from 400° C.to 900° C., from 500° C. to 850° C., from 600° C. to 800° C., from 600°C. to 700° C., and the like. In these and other aspects, thesetemperature ranges also are meant to encompass circumstances where theactivation step is conducted at a series of different temperatures(e.g., an initial temperature, a peak temperature), instead of at asingle fixed temperature, falling within the respective ranges. Forinstance, the activation step can start at an initial temperature, andsubsequently, the temperature of the activation step can be increased tothe peak temperature, for example, a peak temperature in a range from500° C. to 850° C., or from 600° C. to 800° C.

The duration of the activation step is not limited to any particularperiod of time. Hence, this activation step can be conducted, forexample, in a time period ranging from as little as 1 min to as long as12-24 hr, or more. The appropriate activation time can depend upon, forexample, the initial/peak temperature, among other variables. Generally,however, the activation step can be conducted in a time period that canbe in a range from 1 min to 24 hr, from 1 hr to 12 hr, from 2 hr to 8hr, or from 2 hr to 6 hr.

Catalyst activation is ordinarily performed in an oxidizing atmosphere,and the oxidizing atmosphere can comprise air, O₂, N₂O, NO₂, or NO, andany mixture or combination thereof. In some aspects, the activationatmosphere can comprise air (e.g., dry air), while in other aspects, theatmosphere can comprise a mixture of air and nitrogen. If desired, thetitanated chromium/silica catalyst can be reduced using CO or a suitablehydrocarbon. Activation also can be accomplished by exposure to anon-oxidizing atmosphere first, followed by an oxidizing atmosphere, asdescribed in U.S. Pat. No. 11,149,098. Any suitable activation vesselcan be used for the activation step, which can be performed batchwise orcontinuous. For instance, fluidized bed, tray, trickle, and fixed bedvessels and associated techniques can be used for the activation step.

EXAMPLES

The invention is further illustrated by the following examples, whichare not to be construed in any way as imposing limitations to the scopeof this invention. Various other aspects, modifications, and equivalentsthereof, which after reading the description herein, can suggestthemselves to one of ordinary skill in the art without departing fromthe spirit of the present invention or the scope of the appended claims.

Titanium precursors. Approximately 35 g of titanium tetraisopropoxidesolution was added to 200 mL water and stirred for 30 min. Then, waterwas removed by rotary evaporator and the resulting hydrous TiO₂ wasdissolved in an oxalic acid solution with an oxalic acid to titaniummolar ratio of 2:1. This solution is referred to herein as TiO₂-OA.Other titanium precursors were titanium tetraisopropoxide andtitanium(IV) oxysulfate solution, used without further purification.

General procedure for aqueous titanation of a silica support andpreparation of the pre-catalyst. The alkali metal salt was dissolved inwater to form a ˜0.17 M alkali solution. Then, a hydrogen peroxidesolution was added to this alkali solution and stirred for few minutes.Then, the titanium precursor was added at an alkali metal:titanium molarratio in the 0.7:1 to 1.9:1 range to form a homogenous solution. Next,an ammonium hydroxide solution was added to adjust the pH to a desiredvalue in the 4-10 range. Then, a required amount of preformed silica A(typically 5 g) having a pore volume of 1.6 mL/g, a BET surface area of500 m²/g, and a d50 average particle size of 80 μm, was added and ifneeded, the pH was re-adjusted with additional ammonium hydroxidesolution. This mixture was then heated to a desired temperature(typically under reflux conditions, 100° C.) for a specified time(typically 1 hr). The resulting mixture was filtered through a glassfrit by suction, and washed with water and ethanol. The resultingtitanated silica support was then dried at room temperature. About 1 wt.% chromium was deposited onto the dried titanated silica by addition ofchromium(III) acetate hydroxide (CrOAc) dissolved in methanol, followedby drying at room temperature, to form the titanated chromium/silicapre-catalyst.

Catalyst activation. The final titanated Cr(VI)/SiO₂ catalyst wasobtained by activation of the above pre-catalyst in a 4.87-cm(1.88-inch) diameter activator tube by flowing dry air at a rate of0.57-0.75 L/min (1.2-1.6 scfh) and ramping to 650° C. at a rate of 4°C./min and holding at 650° C. for 3 hr.

Polymerization Experiments. The polymerization tests were performed in a2.65 L stainless-steel reactor equipped with a marine stirrer rotatingat 500 rpm. The reactor was surrounded by a steel jacket through whichwater circulated being heated and cooled by hot (steam) and cold (plantwater) heat exchangers to control the reaction temperature. A smallamount of activated catalyst (0.05 to 0.10 g) was first loaded into thereactor under dry nitrogen. Next, 1.2 L of isobutane liquid was addedand the reactor was heated to the set temperature of 105° C. Ethylenewas then added to the reactor, which was maintained at 3.79 MPa (550psig) throughout the course of the experiment. The reaction wascontinued until a productivity of ˜3000 g of polyethylene per g ofcatalyst was reached, as determined by flow controllers measuring theflow of ethylene to the reactor. Once the target productivity wasachieved, the time was noted, the ethylene flow was stopped, the reactorwas cooled and depressurized, and the granular polymer powder wasrecovered. The dry powder was weighed, and catalyst activity wasquantified as grams of polymer produced per gram of solid catalystcharged per hr (g/g/h).

Melt index (MI, g/10 min) was determined in accordance with ASTM D1238at 190° C. with a 2.16 kg weight, I₁₀ (g/10 min) was determined inaccordance with ASTM D1238 at 190° C. with a 10 kg weight, and high loadmelt index (HLMI, 121, g/10 min) was determined in accordance with ASTMD1238 at 190° C. with a 21.6 kg weight. Density can be determined ingrams per cubic centimeter (g/cm³) on a compression molded sample,cooled at 15° C. per minute, and conditioned for 40 hours at roomtemperature in accordance with ASTM D1505 and ASTM D4703.

Molecular weights and molecular weight distributions can be obtainedusing a PL-GPC 220 (Polymer Labs, an Agilent Company) system equippedwith a IR4 detector (Polymer Char, Spain) and three Styragel® HMW-6E GPCcolumns (Waters, MA) running at 145° C. The flow rate of the mobilephase 1,2,4-trichlorobenzene (TCB) containing 0.5 g/L2,6-di-t-butyl-4-methylphenol (BHT) is set at 1 mL/min, and polymersolution concentrations are in the range of 1.0-1.5 mg/mL, depending onthe molecular weight. Sample preparation is conducted at 150° C. fornominally 4 hr with occasional and gentle agitation, before thesolutions is transferred to sample vials for injection. An injectionvolume of 200 μL is used. The integral calibration method is used todeduce molecular weights and molecular weight distributions using aChevron Phillips Chemical Company's HDPE polyethylene resin,MARLEX®BHB5003, as the broad standard. The integral table of the broadstandard is pre-determined in a separate experiment with SEC-MALS. Mn isthe number-average molecular weight, Mw is the weight-average molecularweight, Mz is the z-average molecular weight, My is viscosity-averagemolecular weight, and Mp is the peak molecular weight (location, inmolecular weight, of the highest point of the molecular weightdistribution curve).

Melt rheological characterizations can be performed as follows.Small-strain (less than 10%) oscillatory shear measurements areperformed on an Anton Paar MCR rheometer using parallel-plate geometry.All rheological tests are performed at 190° C. The complex viscosity|η*| versus frequency (ω) data are then curve fitted using the modifiedthree parameter Carreau-Yasuda (CY) empirical model to obtain the zeroshear viscosity—η₀, characteristic viscous relaxation time—τ_(η), andthe breadth parameter—a (CY-a parameter). The simplified Carreau-Yasuda(CY) empirical model is as follows.

${{❘{\eta^{*}(\omega)}❘} = \frac{\eta_{0}}{\left\lbrack {1 + \left( {\tau_{\eta}\omega} \right)^{a}} \right\rbrack^{{({1 - n})}/a}}},$

-   -   wherein: |η*(ω)|=magnitude of complex shear viscosity;        -   η₀=zero shear viscosity;        -   τ_(η)=viscous relaxation time (Tau(η));        -   a=“breadth” parameter (CY-a parameter);        -   n=fixes the final power law slope, fixed at 2/11; and        -   ω=angular frequency of oscillatory shearing deformation.

Details of the significance and interpretation of the CY model andderived parameters can be found in: C. A. Hieber and H. H. Chiang,Rheol. Acta, 28, 321 (1989); C. A. Hieber and H. H. Chiang, Polym. Eng.Sci., 32, 931 (1992); and R. B. Bird, R. C. Armstrong and O. Hasseger,Dynamics of Polymeric Liquids, Volume 1, Fluid Mechanics, 2nd Edition,John Wiley & Sons (1987).

Metal contents, such as the amount of alkali metal, titanium, andchromium present on the catalyst, were determined by ICP analysis on aPerkinElmer Optima 8300 instrument. Samples were ashed in a Thermolynefurnace with sulfuric acid overnight, followed by acid digestion in aHotBlock with HCl and HNO₃ (3:1 v:v).

Examples 1-15

Table 1 summarizes comparative polymerization experiments with variabletitanium loadings and sources/precursors, but with no alkali metalutilized during catalyst preparation. In Example 1, 0.21 g CrOAcdissolved in 5 mL of methanol was added to 5 g preformed silica A, driedat room temperature (RT), and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

In Example 2, 2.22 g TiOSO₄ was added to 20 mL water containing 2.5 g of35 wt. % H₂O₂ solution and stirred for homogenization. Then, ammoniumhydroxide was added to increase the pH of the solution to 10. Next, 5 gpreformed silica A was added and the mixture was heated to 100° C. underreflux for 1 hr. The solids were filtered hot by suction filtrationthrough a glass frit, washed with water and ethanol, and dried at RT.Then, 0.21 g CrOAc dissolved in 5 mL of methanol was added, RT dried,and activated in a flow of dry air in a fluidized bed at 650° C. for 3hr.

In Example 3, 0.60 g Ti(OiPr)₄ was added to 20 mL water containing 2.5 gof 35 wt. % H₂O₂ solution and stirred for homogenization. Then, ammoniumhydroxide was added to increase the pH of the solution to 10. Next, 5 gpreformed silica A was added and the mixture was heated to 100° C. underreflux for 1 hr. The solids were filtered hot by suction filtrationthrough a glass frit, washed with water and ethanol, and dried at RT.Then, 0.21 g CrOAc dissolved in 5 mL of methanol was added, RT dried,and activated in a flow of dry air in a fluidized bed at 650° C. for 3hr.

In Examples 4-5, 0.25 g (for 5 wt. % Ti) or 0.50 g (for 10 wt. % Ti)titanium metal powder was added to a mixture containing 20 g of 30 wt. %H₂O₂ and 5 g of NH₄OH solution and stirred for homogenization (typically1.5-2 hr). Then, more ammonium hydroxide was added to increase the pH ofthe solution to 10. Next, 5 g preformed silica A was added and themixture was heated to at 100° C. under reflux for 1 hr. The solids werefiltered hot by suction filtration through a glass frit, washed withwater and ethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mLof methanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

In Examples 6-11, depending on the concentration of the prepared TiO₂-OAsolution, the amounts added varied from 1.7 mL (for 1 wt. % Ti) to 17 mL(for 10 wt. % Ti). Respectively, the amounts of 35 wt. % H₂O₂ addedvaried from 1.1 g to 10.3 g resulting in H₂O₂/Ti molar ratios of˜10.1-10.8, except Example 6. Then, ammonium hydroxide was added toincrease the pH of the solution to 10. Next, 5 g preformed silica A wasadded and the mixture was heated to 100° C. under reflux for 1 hr. Thesolids were filtered hot by suction filtration through a glass frit,washed with water and ethanol, and dried at RT. Then, 0.21 g CrOAcdissolved in 5 mL of methanol was added, RT dried, and activated in aflow of dry air in a fluidized bed at 650° C. for 3 hr.

For Examples 12-15, 0.60 g Ti(OiPr)₄ was added to a mixture containing50 mL H₂O, 2.5 g of 35 wt. % H₂O₂, and complexing agents 0.50 g glycolicacid (Example 12), or 0.50 g lactic acid (Example 13), or 0.89 g citricacid (Example 14), or 0.53 g oxalic acid (Example 15). Then, ammoniumhydroxide was added to increase the pH of the solution to 10. Next, 5 gpreformed silica A was added and the mixture was heated to 100° C. underreflux for 1 hr. The solids were filtered hot by suction filtrationthrough a glass frit, washed with water and ethanol, and dried at RT.Then, 0.21 g CrOAc dissolved in 5 mL of methanol was added, RT dried,and activated in a flow of dry air in a fluidized bed at 650° C. for 3hr.

The Ti loadings in Table 1, Examples 2-15, varied from 1-10 wt. % byvarying the amounts of the Ti-source added. The pre-catalysts wereprepared at a pH of 10, heated to 100° C. under reflux for a period of 1hr. The activated catalysts showed an increasing HLMI potential with Tiloading, but higher Ti loadings of 7-10 wt. % were needed to reach HLMIvalues over 30.

TABLE 1 Ti Prod. Activity Ex H₂O₂/Ti Ti Source wt. % (g/g) (g/g/h) HLMII₁₀ MI 1 None None, Control Run 0 2892 2066 6.3 1.2 0.06 2 12.3 TiOSO₄2.0 2914 2797 12.0 2.3 0.10 3 12.3 Ti(OiPr)₄ 2.0 2915 2670 15.1 3.0 0.164 33.8 Ti powder 5.0 3060 2661 19.1 3.8 0.13 5 29.5 Ti powder 10.0 29122329 33.5 7.1 0.44 6 21.1 TiO₂—OA 8.0 4119 5747 34.9 6.9 0.34 7 10.8TiO₂—OA 1.0 2954 2496 7.8 1.5 0.04 8 10.3 TiO₂—OA 5.0 3173 3282 14.0 2.30.10 9 10.1 TiO₂—OA 7.0 2948 3023 32.2 6.5 0.35 10 10.2 TiO₂—OA 8.5 30202970 32.9 6.3 0.30 11 10.1 TiO₂—OA 10.0 2971 2764 39.3 7.9 0.40 12 12.3Ti(OiPr)₄ ₊ Glycolic Acid 2.0 2994 2461 14.0 2.7 0.10 13 12.3 Ti(OiPr)₄₊ Lactic Acid 2.0 2904 2471 11.7 1.9 0.10 14 12.3 Ti(OiPr)₄ ₊ CitricAcid 2.0 2949 2440 15.3 3.0 0.13 15 12.3 Ti(OiPr)₄ ₊ Oxalic Acid 2.02906 3170 13.2 2.6 0.10

Examples 16-27

Table 2 summarizes catalyst preparation and polymerization experimentswith variable titanium loadings using TiO₂-OA as the titaniumsource/precursor, and with Na₂SiO₃ utilized during catalyst preparation(molar ratios of H₂O₂/Ti and Na/Ti are listed in Table 2). In Examples16-27, 0.55-2 g Na₂SiO₃ was added to a solution containing 10 mL water,1-16.6 g of 35 wt. % H₂O₂, and 5 g of ammonium hydroxide. After stirringfor a few min, the TiO₂-OA solution (depending on the concentration ofthis solution prepared, the amounts varied from 3.3 g for 2 wt. % Ti to15.33 g for 9 wt. % Ti) was added. Next, 5 g preformed silica A wasadded and if needed, pH was readjusted to 10 and the mixture was heatedto 100° C. under reflux for 1 hr. The actual amounts of Na₂SiO₃, H₂O₂,and silica in grams are summarized in Table 2. The solids were filteredhot by suction filtration through a glass frit, washed with water andethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mL ofmethanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr. The polymerization experiments inTable 2 reveal a 2-3× increase in the HLMI potential compared tocatalysts prepared without a sodium source (see Examples 6-11 in Table1), signifying the beneficial and unexpected role of addition of sodiumduring catalyst preparation.

TABLE 2 ^(g)Na₂SiO₃/^(g)H₂O₂/ Ti H₂O₂/ Alkali/ Prod. Activity Ex^(g)SiO₂ wt. % Ti Ti (g/g) (g/g/h) HLMI I₁₀ MI 16 2/16.6/5 5.0 32.7 1.182866 2773 44.4 9.7 0.66 17 2/16.6/5 2.6 62.9 2.27 2966 2825 35.4 7.50.53 18 1/16.6/5 5.0 32.7 0.59 2948 3845 44.4 9.0 0.51 19 0.55/16.6/55.0 32.7 0.33 2921 4274 42.7 9.0 0.52 20 1/5/5 5.0 9.8 0.59 2705 427160.9 13.5 0.93 21 1/2.5/5 5.0 4.9 0.59 2677 2722 44.0 9.4 0.59 22 1/1/55.0 1.9 0.59 2981 3313 30.0 6.1 0.3 23 1/10/5 5.0 19.7 0.59 2611 184328.7 5.8 0.3 24 1/16.6/5 2.8 60.3 1.06 3292 4031 23.8 4.7 0.22 251/16.6/5 4.7 35.9 0.63 3220 4493 42.5 8.6 0.52 26 1/16.6/5 7.5 22.5 0.393227 3458 57.6 12.3 0.80 27 1/16.6/5 8.7 19.4 0.34 3159 3213 62.0 12.80.83

Examples 28-41

Table 3 summarizes catalyst preparation and polymerization experimentswith variable titanium loadings using a TiOSO₄ solution as the titaniumsource/precursor, and with NaHCO₃ or NaCl utilized during catalystpreparation (other sodium precursors can be used, such as sodiumcarbonate). In Examples 28-35, 0.05 g (Example 30), or 0.14 g (Example29), or 0.29 g (Examples 28 and 32-35), or 0.58 g (Example 31), or 0.29g (Example 28) of NaHCO₃ was dissolved in 20 mL water. Then, 2.5 g of 35wt. % H₂O₂ (for Examples 28-32), or 1.1 g of 35 wt. % H₂O₂ (for Example33), or 4 g of 35 wt. % H₂O₂ (for Example 34), or 5.8 g of 35 wt. % H₂O₂(for Example 35) was added. Then, TiOSO₄ (˜1.1 g for 1 wt. % Ti, 2.2 gfor 2 wt. % Ti, 4 g for 3.5 wt. % Ti, and 5.8 g for 5 wt. % Ti) wasadded. Then, ammonium hydroxide was added to increase the pH of thesolution to 10. Next, 5 g preformed silica A was added and the mixturewas heated to 100° C. under reflux for 1 hr. The solids were filteredhot by suction filtration through a glass frit, washed with water andethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mL ofmethanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

In Examples 36-41, 0.05 g (Example 36), or 0.10 g (Example 37), or 0.20g (Example 38), or 0.35 g (Example 39), or 0.50 g (Example 40), or 0.80g (Example 41), of NaCl was dissolved in 20 mL water. Then, 35 wt. %H₂O₂ 0.5 g (Example 36), or 1.0 g (Example 37), or 2.0 g (Example 38),or 3.5 g (Example 39), or 5.0 g (Example 40), or 8.0 g (Example 41) wasadded. Then, TiOSO₄ (˜0.55 g for 0.5 wt. % Ti, 1.1 g for 1 wt. % Ti, 2.2g for 2 wt. % Ti, 3.9 g for 3.5 wt. % Ti, 5.8 g for 5 wt. % Ti, and 9.3g for 8 wt. % Ti) was added. Then, ammonium hydroxide was added toincrease the pH of the solution to 10. Next, 5 g preformed silica A wasadded and the mixture was heated to 100° C. under reflux for 1 hr. Thesolids were filtered hot by suction filtration through a glass frit,washed with water and ethanol, and dried at RT. Then, 0.21 g CrOAcdissolved in 5 mL of methanol was added, RT dried, and activated in aflow of dry air in a fluidized bed at 650° C. for 3 hr.

The polymerization experiments in Table 3 demonstrate, surprisingly,that HLMI values in excess of 30 were readily achieved with only 2 wt. %titanium, under various catalyst preparation conditions. ICPcompositional analysis also is summarized in Table 3. This informationis shown graphically in FIG. 1 , which is a plot of the HLMI of thepolymer versus the number of titanium atoms per square nanometer for thecontrol titanated chromium/silica catalysts and for the titanatedchromium/silica catalysts of Examples 28-41.

The control catalysts in FIG. 1 were prepared from a silica having asurface area of 480 m²/g, a pore volume of 1.67 mL/g, and an averageparticle size of 75 μm. Ten gram samples of this silica were placed in amuffle furnace at 200° C. for 12 hr. Then, these silica samples werecaptured in an air-tight bottle while the silica was still hot. Thesilica samples were then slurried in dry isopropyl alcohol, followed bythe addition of titanium isopropoxide under constant stirring for 1 hr,after which a methanol solution of basic chromic acetate was added toresult in 1 wt. % chromium for each catalyst. The slurry was dried undervacuum at 100° C. for 2 hr. The titanium isopropoxide was added in anamount to equal a set target ranging from 0.25 wt. % to 8 wt. % oftitanium, based on the weight of the silica. Using the silica surfacearea (m²/g) and converting to nm², these weight percentages wereultimately converted to atoms of Ti/nm² and resulted in the control linein FIG. 1 (for example, 2 wt. % titanium is 0.52 Ti/nm²).

Invention set 1 in FIG. 1 is Examples 36-41, and Invention set 2 isExamples 28-35, where the surface area is 500 m²/g (2 wt. % titanium is0.50 Ti/nm²). At equivalent titanium loadings, the titanatedchromium/silica catalysts of Examples 36-41 resulted in significantlyhigher HLMI values as compared to the control, with unexpected increasesof ˜18 to 100% in HLMI at the same titanium loading. At low titaniumloadings (e.g., 1-2 wt. % titanium), Invention set 2 also resulted insignificantly higher HLMI values as compared to the control, withunexpected increases of ˜60 to 90%. The higher titanium loading examplesof Invention set 2 were comparable to the control; it is believed that alow Na/Ti molar ratio was the cause, and that higher HLMI values wouldhave resulted if a higher ratio was used.

TABLE 3 H₂O₂/ Alkali Alkali/ Ti Prod. Activity Activated Catalyst (wt.%) Ex Ti Source Ti wt % (g/g) (g/g/h) HLMI I₁₀ MI Ti Na Cr 28 12.3NaHCO₃ 1.65 2.0 2863 2526 38.4 8.1 0.50 1.38 0.20 0.77 29 12.3 NaHCO₃0.80 2.0 2865 2233 23.4 4.9 0.26 1.57 0.09 0.80 30 12.3 NaHCO₃ 0.28 2.02917 2349 13.1 2.5 0.10 1.67 0.05 0.79 31 12.3 NaHCO₃ 3.30 2.0 2795 229844.7 9.5 0.60 1.39 0.35 0.83 32 12.3 NaHCO₃ 1.65 2.0 2956 2838 38.2 8.00.50 1.65 0.17 0.77 33 10.8 NaHCO₃ 3.30 1.0 3036 2698 24.7 5.0 0.20 0.710.27 0.92 34 11.3 NaHCO₃ 0.94 3.5 2937 2073 40.8 8.5 0.50 2.68 0.13 0.7335 11.4 NaHCO₃ 0.66 5.0 2676 2632 49.6 9.9 0.60 3.68 0.11 0.71 36 9.8NaCl 1.64 0.5 3089 3064 19.3 3.8 0.16 0.40 0.12 0.85 37 9.8 NaCl 1.641.0 2753 2430 24.3 4.8 0.25 0.73 0.13 0.73 38 9.8 NaCl 1.64 2.0 30582759 30.9 5.3 0.36 1.37 0.19 0.77 39 9.8 NaCl 1.64 3.5 2957 3113 48.510.3 0.60 2.42 0.21 0.69 40 9.8 NaCl 1.64 5.0 3043 3147 75.2 15.7 1.003.76 0.28 0.72 41 9.8 NaCl 1.64 8.0 2925 2639 76.4 16.0 1.10 5.33 0.330.71

Examples 42-46

Table 4 summarizes catalyst preparation and polymerization experimentswith a constant titanium loading using Ti(OiPr)₄ and complexing acids asthe titanium source/precursor, and with NaCl utilized during catalystpreparation. In Examples 42-46 (compare with Examples 3 and 12-15), 0.2g NaCl was dissolved in 50 mL water. Then, 2.5 g of 35 wt. % H₂O₂ andcomplexing agents 0.50 g glycolic acid (Example 44), or 0.50 g lacticacid (Example 43), or 0.89 g citric acid (Example 45), or 0.53 g oxalicacid (Example 46) were also added and solubilized. Then, 0.60 gTi(OiPr)₄ was added and the pH of the solution was increased to 10 withaddition of ammonium hydroxide. The molar ratio of H₂O₂/Ti and Alkali/Tiwas 12.3:1 and 1.64:1, respectively. Next, 5 g preformed silica A wasadded and the mixture was heated to 100° C. under reflux for 1 hr. Thesolids were filtered hot by suction filtration through a glass frit,washed with water and ethanol, and dried at RT. Then, 0.21 g CrOAcdissolved in 5 mL of methanol was added, RT dried, and activated in aflow of dry air in a fluidized bed at 650° C. for 3 hr.

The polymerization experiments of Examples 42-46 in Table 4 demonstratethat HLMI values of 32-45 were readily achieved with only 2 wt. %titanium, whereas comparative Examples 3 and 12-15 produced polymerswith HLMI values of only 11-15.

TABLE 4 Ti Prod. Activity Ex Ti Source wt % (g/g) (g/g/h) HLMI I₁₀ MI 42Ti(OiPr)₄ 2 2923 3218 44.9 9.7 0.60 43 Ti(OiPr)₄₊ Lactic Acid 2 29243161 38.8 8.3 0.50 44 Ti(OiPr)₄₊ Glycolic 2 2948 2406 32.5 6.7 0.36 Acid45 Ti(OiPr)₄₊ Citric Acid 2 2997 3361 40.2 8.6 0.50 46 Ti(OiPr)₄₊ Oxalic2 2955 2859 38.0 8.0 0.50 Acid

Examples 47-54

Table 5 summarizes catalyst preparation and polymerization experimentswith various titanium loadings using TiO₂-OA as the titaniumsource/precursor, and with NaOH utilized during catalyst preparation. InExamples 47-54, to 20 mL water containing 2.5 g of 35 wt. % H₂O₂ and 3.3g TiO₂-OA solution (for 2 wt. % Ti, Examples 47-51 and 54) or 5.9 gTiO₂-OA solution (for 3.5 wt. % Ti, Examples 52-53), 1N NaOH solutionwas added in the amounts shown in Table 5. Then, ammonium hydroxide wasadded to increase the pH of the solution to 10 for Examples 47-53. ForExample 54, no ammonium hydroxide was added; the pH was increased to 10with 1N NaOH solution. Next, 5 g preformed silica A was added and themixture was heated to 100° C. under reflux for 1 hr. The solids werefiltered hot by suction filtration through a glass frit, washed withwater and ethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mLof methanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

As shown in Table 5, the HLMI values of the polymers produced from thetitanated chromium/silica catalysts increased with increasing Na contentduring catalyst preparation (see Examples 47-51). Example 54 did nothave any polymerization activity, and while not wishing to be bound bytheory, it is believed that ammonium hydroxide plays an important rolein both increasing pH as well as aiding/improving titanium incorporation(more effective titanation).

TABLE 5 mL NaOH H₂O₂/ Alkali/ Ti Prod. Activity Ex (1N) Ti Ti wt % (g/g)(g/g/h) HLMI I₁₀ MI 47 0.45 12.32 0.20 2.0 2998 3634 11.7 2.1 0.09 480.85 12.32 0.40 2.0 2849 3196 20.3 4.0 0.20 49 1.65 12.32 0.79 2.0 29002617 32.2 6.7 0.40 50 3.30 12.32 1.59 2.0 3141 3732 39.5 8.5 0.50 516.50 12.32 3.16 2.0 3015 3173 47.1 10.6 0.70 52 3.50 12.32 1.68 3.5 31373655 48.3 10.4 0.70 53 7.00 7.04 1.91 3.5 2513 908 48.8 11.7 0.91 5422.5 12.32 10.77 2 0 0 0 0 0

Examples 55-57

Table 6 summarizes catalyst preparation and polymerization experimentswith a fixed titanium loading and TiO₂-OA titanium source/precursor, anddifferent sodium sources utilized during catalyst preparation. InExamples 55-57, to 20 mL water containing 2.5 g of 35 wt. % H₂O₂ and 3.3g TiO₂ solution (for 2 wt. % Ti), 0.29 g NaHCO₃ for Example 55, or 0.26g NaOAc for Example 56, or 0.23 g Na₂C₂₀₄ for Example 57, was added, asshown in Table 6. Then, ammonium hydroxide was added to increase the pHof the solution to 10. Next, 5 g preformed silica A was added and themixture was heated to 100° C. under reflux for 1 hr. The solids werefiltered hot by suction filtration through a glass frit, washed withwater and ethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mLof methanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

The polymerization experiments of Examples 55-57 in Table 6 demonstratethat HLMI values of 30-40 were readily achieved with only 2 wt. %titanium, regardless of the alkali metal source/precursor.

TABLE 6 Alkali H₂O₂/ Alkali/ Ti Prod. Activity Ex Precursor (g) Ti Ti wt% (g/g) (g/g/h) HLMI I₁₀ MI 55 NaHCO₃ (0.29 g) 12.3 1.65 2 2921 269640.5 8.6 0.50 56 NaOAc 12.3 1.52 2 2898 2973 30.8 6.4 0.35 (0.26 g) 57Na₂C₂O₄ (0.23 g) 12.3 1.64 2 3018 3043 32.6 6.9 0.40

Examples 58-68

Table 7 summarizes catalyst preparation and polymerization experimentswith potassium salts and Table 8 summarizes catalyst preparation andpolymerization experiments with lithium salts. Pre-catalysts wereprepared at a pH of 10 using ammonium hydroxide, heated to 100° C. underreflux for 1 hr, and the titanium source/precursor was TiO₂-OA. ForExamples 58-62, 2.5 g of 35 wt. % H₂O₂ was added to 20 mL water, and aTiO₂-OA solution (3.3 g for a 2 wt. % Ti, Examples 58 and 60-62, or 8.52g for 5 wt. % Ti, Example 59) was added. Then, 3.5 mL 1N KOH solution(for Examples 58-59), or 1.9 mL 1N KOH (for Example 60), or 2.8 mL 1NKOH solution (for Example 61), or 0.24 g K₂CO₃ (for Example 62) wasadded. Then, ammonium hydroxide was added to increase the pH of thesolution to 10. Next, 5 g preformed silica A was added and the mixturewas heated to 100° C. under reflux for 1 hr. The solids were filteredhot by suction filtration through a glass frit, washed with water andethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mL ofmethanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

For Examples 63-68, to 50 mL water containing 2.5 g of 35 wt. % H₂O₂ and5 g NH₄OH, 20 wt. % lithium polysilicate solution in the followingamounts was added: 0.71 g (Example 63), 1.64 g (Example 64), 2.50 g(Example 65), 3.30 g (Example 66) 4.20 g (Example 67) and 5.0 g (Example68). Then, 3.3 g of TiO₂-OA solution corresponding to 2 wt. % Ti wasadded, and if needed, ammonium hydroxide was added to increase the pH ofthe solution to 10. Next, 5 g preformed silica A was added and themixture was heated to 100° C. under reflux for 1 hr. The solids werefiltered hot by suction filtration through a glass frit, washed withwater and ethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mLof methanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

The polymerization experiments of Examples 58-68 in Tables 7-8demonstrate that, unexpectedly, potassium and lithium usage duringcatalyst preparation also produced polymers having HLMI values of over30 with only 2 wt. % titanium, in a manner similar to sodium. Tables 7-8also summarize the results of ICP compositional analysis of theactivated titanated chromium/silica catalysts: 0.78-0.92 wt. % chromium,0.9-3 wt. % titanium, 0.4-0.8 wt. % potassium, and 0.03-0.2 wt. %lithium.

TABLE 7 H₂O₂/ Alkali Ti Prod. Activity Ex Ti Source K/Ti wt % (g/g)(g/g/h) HLMI I₁₀ MI 58 12.32 KOH 1.67 2.0 2772 3394 40.3 8.6 0.6 59 7.04KOH 0.67 3.5 2979 3372 34.0 7.0 0.4 60 12.32 KOH 0.90 2.0 2638 4059 33.67.0 0.4 61 12.32 KOH 1.34 2.0 3076 2818 37.4 7.8 0.5 62 12.32 K₂CO₃ 1.662.0 3057 2983 34.5 7.5 0.45 Activated Catalyst (wt. %) Ex Ti K Cr 581.69 0.77 0.89 59 2.97 0.73 0.89 60 1.51 0.45 0.92 61 1.70 0.70 0.87 62— — —

TABLE 8 Ti Prod. Activity Ex H₂O₂/Ti Li/Ti wt % (g/g) (g/g/h) HLMI I₁₀MI 63 12.32 0.52 2 2905 4251 25.7 5.2 0.3 64 12.32 1.20 2 3048 4253 29.05.9 0.3 65 12.32 1.83 2 3252 4151 35.1 7.2 0.4 66 12.32 2.42 2 2982 305930.0 6.1 0.3 67 12.32 3.08 2 3003 2611 37.0 7.6 0.4 68 12.32 3.67 2 30052752 31.4 6.3 0.3 Activated Catalyst (wt. %) Ex Ti Li Cr 63 1.19 0.030.87 64 1.09 0.06 0.83 65 1.00 0.08 0.80 66 1.20 0.17 0.80 67 1.21 0.200.81 68 0.91 0.19 0.78

Examples 69-78

Table 9 summarizes the effect of temperature on aqueous titanation whileusing NaOH or sodium silicate as the alkali metal source/precursor, andat Ti loadings of either 2 or 5 wt. %. Catalyst mixtures were heated atdifferent temperatures from RT to reflux conditions (100° C.). TheH₂O₂/Ti molar ratio was 32.7:1 and 12.3:1, respectively, for a Tiloading of 5 and 2 wt. %. Similarly, the Alkali/Ti molar ratio was0.59:1 and 1.58:1, respectively, for a Ti loading of 5 and 2 wt. %. TheTi-source/precursor was TiO₂-OA. The melt index potential of thetitanated chromium/silica catalysts prepared at lower temperatures canbe improved by allowing a longer time for the catalyst mixture to reactprior to separating the liquids from the solids and subsequent drying.

For Examples 69-73, to 20 mL water containing 16.6 g of 35 wt. % H₂O₂and 5 g NH₄OH, 1 g sodium silicate solution was added. Then, 8.5 g ofTiO₂-OA solution corresponding to 5 wt. % Ti was added, and if needed,ammonium hydroxide was added to increase the pH of the solution to 10.Next, 5 g preformed silica A was added and the mixture was heated at thetemperatures for the time periods shown in Table 9. The solids werefiltered hot by suction filtration through a glass frit, washed withwater and ethanol, and dried at RT. Then, 0.21 g CrOAc dissolved in 5 mLof methanol was added, RT dried, and activated in a flow of dry air in afluidized bed at 650° C. for 3 hr.

For Examples 74-78, to 17 ml of water containing 2.5 g of 35 wt. % H₂O₂,33 mL of 0.1N NaOH solution was added, and then 3.3 g of TiO₂-OAsolution corresponding to 2 wt. % Ti. Then, ammonium hydroxide was addedto increase the pH of the solution to 10. Next, 5 g preformed silica Awas added and the mixture was heated at the temperatures for the timeperiods shown in Table 9. The solids were filtered hot by suctionfiltration through a glass frit, washed with water and ethanol, anddried at RT. Then, 0.21 g CrOAc dissolved in 5 mL of methanol was added,RT dried, and activated in a flow of dry air in a fluidized bed at 650°C. for 3 hr.

TABLE 9 Temp Time Alkali Ti Prod. Activity Ex ° C. hr Source wt % (g/g)(g/g/h) HLMI I₁₀ MI 69 RT 2.0 Na₂SiO₃ 5 2733 3279 9.7 1.8 0.05 70 40 2.0Na₂SiO₃ 5 2893 3543 10.5 2.0 0.09 71 60 1.5 Na₂SiO₃ 5 2961 4131 17.6 3.50.12 72 80 1.0 Na₂SiO₃ 5 2732 3152 60.0 13.0 0.92 73 100 1.0 Na₂SiO₃ 53027 4127 42.1 8.3 0.44 74 RT 96 NaOH 2 2879 3455 4.4 0.6 0.00 75 40 24NaOH 2 2870 4783 28.5 5.8 0.30 76 60 15 NaOH 2 2987 2987 29.2 6.1 0.3077 80 4.0 NaOH 2 2915 3269 32.0 6.6 0.40 78 100 1.0 NaOH 2 3141 373239.5 6.6 0.50

Examples 79-84

Table 10 summarizes the effect of pH on aqueous titanation while usingNaOH as the alkali metal source/precursor, and at a Ti loading of 2 wt.%. The pH was varied in the 4-10 range in the presence of sodium andammonium hydroxide. Remarkably, all the titanated chromium/silicacatalysts showed HLMI potential encompassing a commercially relevantrange of 25-40, with mild titanium leaching noticed only at lower pH(e.g., pH range of 4-6). Leaching can be determined by ICP analysis ofthe filtrate, or addition of hydrogen peroxide to the filtrate, whichresults in a color change. The H₂O₂/Ti molar ratio was 12.3:1 and theAlkali/Ti molar ratio was 1.58:1. The Ti-source/precursor was TiO₂-OA.

For Examples 79-84, to 17 mL of water containing 2.5 g of 35 wt. % H₂O₂,33 mL of 0.1N NaOH solution was added, and then 3.3 g of TiO₂-OAsolution corresponding to 2 wt. % Ti. Then, ammonium hydroxide was addedto increase the pH of the solution to 4 (for Example 84), 6 (for Example83), 7 (for Example 82), 8 (for Example 81), 9 (for Example 80) and 10(for Example 79). Next, 5 g preformed silica A was added and the mixturewas heated to 100° C. under reflux for 3 days for Example 84, or 21 hrfor Example 83, or 15 hr for Example 82, or 2 hr for Examples 80-81, or1 hr for Example 79. Thus, for a pH range of 8-10, 1-2 hr may besufficient, but at lower pH values in the 4-8 range, a longer time isneeded. Note, unexpectedly, a neutral pH of 7 can be utilized, ifdesired.

The solids were filtered hot by suction filtration through a glass frit,washed with water and ethanol, and dried at RT. Then, 0.21 g CrOAcdissolved in 5 mL of methanol was added, RT dried, and activated in aflow of dry air in a fluidized bed at 650° C. for 3 hr.

TABLE 10 Ti Prod. Activity Ex pH wt % (g/g) (g/g/h) HLMI I₁₀ MI 79 10 23141 3732 39.5 6.6 0.50 80 9 2 2983 2435 36.5 7.8 0.50 81 8 2 2928 305544.7 9.8 0.60 82 7 2 2956 3260 35.6 7.6 0.50 83 6 2 2896 3546 33.1 7.20.40 84 4 2 3315 6215 26.7 5.2 0.30

Examples 85-86

Table 11 demonstrates that chromium can be added along with thetitanium, as opposed to loading chromium during the last stage ofcatalyst preparation, with the same beneficial improvement in polymerHLMI. In Examples 85-86, 0.20 g chromium(III) acetate hydroxide wasdissolved in 20 mL water, then either 33 mL of 0.1N NaOH solution (forExample 85) or 0.29 g NaHCO₃ (for Example 86) was added. Then, 2.5 g of35 wt. % H₂O₂ was added, followed by 3.3 g of TiO₂-OA solutioncorresponding to 2 wt. % Ti (for Example 85) or 2.2 g TiOSO₄corresponding to 2 wt. % Ti (for Example 86), and the pH of the mixturewas adjusted to 10 with addition of NH₄OH. After stirring for few min, 5g preformed silica A was added and heated to 100° C. under reflux for 1hr. The catalyst was then filtered, washed with water and ethanol. Thedried catalyst was activated at 650° C. for 3 hr in dry air in afluidized bed.

TABLE 11 Ti Prod. Activity Ex H₂O₂/Ti Na/Ti wt % (g/g) (g/g/h) HLMI I₁₀MI 85 12.3 1.58 2 2905 3384 35.5 7.4 0.40 86 12.3 1.65 2 2889 3502 46.89.9 0.60

Examples 87-88

In Examples 87-88, 1 g Na₂SiO₃ was added to a solution containing 10 mLwater, 16.6 g of 35 wt. % H₂O₂, and 5 g of ammonium hydroxide. Afterstirring for few min, a TiO₂-OA solution was added, followed by 5 g of a0.5 wt. % chromium/silica catalyst, and if needed, the pH was readjustedto 10 and the mixture was heated to 100° C. under reflux for 1 hr. Theamounts of Na₂SiO₃, H₂O₂ and SiO₂ in grams are shown in Table 12. Thesolids were filtered hot by suction filtration through a glass frit,washed with water and ethanol, and dried at RT, then activated in a flowof dry air in a fluidized bed at 650° C. for 3 hr. The polymerizationexperiment using the catalyst of Example 87 revealed a lower HLMIpotential (˜20 HLMI) compared to titanated chromium/silica catalystsprepared with a silica starting material (see Example 18 in Table 12)under similar conditions. While not wishing to be bound by theory, it isbelieved that the lower HLMI potential of Example 87 may be attributedto various factors including lower pore volume of the support and lowerchromium loading (0.5 wt. %). Titanation without sodium silicate(Examples 88) using the 0.5 wt. % chromium/silica catalyst had only aHLMI potential of 11.5, again signifying the important role of thealkali metal for effective titanation.

TABLE 12 ^(g)Na₂SiO₃/^(g)H₂O₂/ Ti H₂O₂/ Alkali/ Prod. Activity Ex^(g)SiO₂ wt % Ti Ti (g/g) (g/g/h) HLMI I₁₀ MI 18 1/16.6/5 5 32.7 0.592948 3845 44.4 9.00 0.51 87 1/16.6/5 5 32.7 0.59 2933 2514 20.1 3.730.16 88 0/16.6/5 5 32.7 0 2473 2433 11.5 2.08 0.1

Examples 89-107

With the exception of zinc, Table 13 demonstrates that divalent andtrivalent metal ions during aqueous titanation do not provide the samebenefit as alkali metals, which can form titanated chromium/silicacatalysts with HLMI potentials of ˜30-50. Divalent metal cationsincluding Mg (Example 89), Ba (Examples 90-92), Sr (Examples 93-97), andZn (Examples 98-102, 107A-107B), and trivalent metal cations including B(Examples 103-105) and Al (Example 106) were tested. The hydroxides ofBa and Sr were sparingly soluble. MgSO₄, Zn(NO₃)₂, H₃BO₃, and AlCl₃ wererespectively used as Mg, Zn, B and Al sources (see Table 13). The Tiloading in these examples was 2 wt. % and the H₂O₂/Ti molar ratio was12.3:1. The resulting titanated chromium/silica catalysts, thoughactive, showed generally poor HLMI potential, mostly in the range of10-15. The exception was zinc examples 107A-107B (HLMI values of ˜30),where in addition to adding ammonium hydroxide to increase the pH to˜10, 0.5 g ammonium sulfate also was added.

TABLE 13 Alkali Prod. Activity Ex Source pH M^(n+)/Ti (g/g) (g/g/h) HLMII₁₀ MI  89 MgSO₄ 8 1.67 2967 2212 14.9 2.9 0.10  90 Ba(OH)₂ 10 0.32 29172941 11.3 2.1 0.08  91 10 0.63 3053 2220 10.3 1.9 0.07  92 10 1.26 29931910 7.6 1.4 0.03  93 Sr(OH)₂ 10 0.18 2929 2407 12.2 2.3 0.10  94 100.36 2957 2289 12.0 2.3 0.10  95 10 0.64 2864 3014 15.0 3.0 0.10  96 100.83 2929 2476 11.9 2.3 0.10  97 10 1.00 2978 2305 15.6 3.0 0.20  98Zn(NO₃)₂ 10 0.32 2980 2194 13.9 2.7 0.10  99 10 0.80 3016 2276 20.9 4.00.20 100 10 1.61 2879 1754 17.4 3.5 0.20 101 10 2.41 2967 2107 17.5 3.50.20 102 10 4.02 3051 1979 16.9 3.3 0.10 103 H₃BO₃ 10 0.77 2953 3730 7.91.3 0.03 104 10 1.63 3011 3441 9.0 1.6 0.06 105 10 3.33 2950 3133 8.81.6 0.05 106 AlCl₃ 7 0.81 3081 5688 14.5 2.5 0.10 107A Zn(NO₃)₂ 9.4 0.533172 3403 31.2 6.4 0.32 107B 10 0.53 3199 4411 28.9 5.6 0.27

Examples 108-122

The amount of sodium was varied in Examples 108-122. First, 25 of water,1-4 g of H₂O₂ (30-35%) and 1-4 g TiOSO₄ solutions were mixed at themolar ratio of H₂O₂/Ti listed in Table 14. Then, sodium hydroxide orNaNO₃ or a combination of both were added as the sodium source to reachthe listed Na/Ti ratio. Following that, an ammonium source (ammoniumhydroxide or ammonium sulfate or ammonium carbonate) was added.Depending on the ammonium source and sodium source, the pH of the finalmixture was in the range of 4-10.5. For Examples 114-116, a constantratio of NH₄ ⁺/Ti of 1.92 was maintained and no pH was measured, and forExample 121, the ammonium source was ammonium carbonate. Next, 5 g ofpreformed silica A was added to the above solution and refluxed at 100°C. for a period of 1 hr. The color of the slurry changed from yellow tocolorless or to faint yellow. The support was filtered, washed withwater and ethanol, and 5 mL of chromium(III) acetate in methanol (1 mgCr/mL) was added and dried at room temperature. Activation was carriedout at 650° C. for a period of 3 hr and the polymerization results arepresented in Table 14. Unexpectedly, very high levels of sodium (Na/Ti)still resulted in high polymer HLMI values (see also Table 5 above).

TABLE 14 H₂O₂/ Na/ Ti Prod. Activity Ex pH Ti Ti wt % (g/g) (g/g/h) HLMII₁₀ MI 108 10 9.4 0.13 3.5 3025 3525 23.2 4.7 0.25 109 10 9.4 0.26 3.53011 3409 35.5 7.5 0.41 110 10 9.4 0.55 3.5 2964 3066 45.6 9.7 0.61 11110 9.4 0.93 3.5 2874 3135 61.9 13.1 0.86 112 10 9.4 1.60 3.5 2989 373684.0 17.8 1.26 113 10 9.4 6.85 3.5 2904 1834 52.3 11.6 0.83 114 12.363.36 2 2979 3136 11.3 2.2 0.10 115 12.36 4.80 2 3034 3166 24.3 5.0 0.25116 12.36 5.76 2 2861 2470 49.5 10.6 0.70 117 10 9.4 2.88 3.5 3035 252953.5 11.7 0.81 118 10 9.4 2.84 3.5 2937 3422 68.3 14.1 1.07 119 10.5 6.730.1 3.23 3221 5204 26.8 5.4 0.28 120 8.7 6.9 10.66 3.14 3166 4166 49.810.7 0.64 121 7.1 6.9 21.5 3.14 3205 2987 50.9 10.9 0.73 122 6.7 5.126.1 1 3120 3132 32.3 6.7 0.41 Activated Catalyst (wt. %) Ex Ti Na Cr114 2.1 0.16 0.99 115 2.4 0.15 0.84 116 2.6 0.40 1.02 117 3.8 1.06 1.03118 3.7 1.05 0.86 119 2.9 0.31 0.99 120 3.7 0.14 0.97 121 2.7 1.05 0.87122 1.0 0.89 1.16

Examples 123-130

Examples 123-130 were performed without ammonium hydroxide and aresummarized in Table 15. Sodium silicate was mixed with 40 g water and2-4 g H₂O₂ (30-35%), then 2-4 g TiOSO₄ solution was added, except forExample 126, which used potassium titanium oxalate as the titaniumsource and the pH was adjusted to 6.7 with dilute HCl before silicaaddition. For Examples 123-127, the sodium source was a mixture ofsodium silicate and NaOH, while for Examples 128-130, the sodium sourcewas a mixture of NaOH and NaNO₃. Next, 5 g of preformed silica A wasadded to the above solution and refluxed at 100° C. for a period of 1-3hr. The yellow color of the slurry remained the same throughout thepreparation. The support was filtered, washed multiple times with waterand chromium(III) acetate in methanol was added and dried at roomtemperature. For Example 127, the filtered support was redispersed in500 mL deionized water, and the pH was adjusted with acid (nitric oracetic) to remove excess sodium. Activation was carried out at 650° C.for a period of 3 hr and the polymerization results are presented inTable 15. Unexpectedly, ammonium hydroxide was not required to achievevery high polymer HLMI values.

TABLE 15 H₂O₂/ Na/ Ti Prod. Activity Activated Catalyst (wt. %) Ex pH TiTi wt % (g/g) (g/g/h) HLMI I₁₀ MI Ti Na Cr 123 4.9 12.36 8.0 2 2996 196525.3 5.2 0.30 2.15 0.65 0.86 124 4.5 10.97 7.9 3.6 3005 2134 30.8 6.60.40 3.49 0.74 1.02 125 4.9 10.97 8.3 3.6 2798 1519 27.5 5.7 0.34 1.610.93 0.80 126 6.7 7.05 4.6 3.6 3050 3327 25.3 5.2 0.25 3.33 0.93 0.92127 5.92 9.0 3.5 2931 3642 28.8 5.5 0.25 2.5 0.42 1.06 128 4.5 10.8725.2 2 3224 3504 41.8 9.3 0.60 129 ~7 6.9 29.9 3.14 3178 2498 36.5 7.90.50 1.4 1.3 1.1 130 8.6 6.9 15.8 3.14 2929 3265 22.8 4.6 0.23 2.1 1.31.0

Examples 131-143

Examples 131-143 were performed with sodium hydroxide and variousorganic acids and bases (e.g., amines, organic tert-ammonium hydroxide,amino acids, glycols, hydroxy acids). The pH of the mixture was adjustedwith either organic acids or bases or sodium hydroxide. Example 131 wasprepared in the absence of organic acids or bases by mixing 50 g H₂O,2.2 g H₂O₂ and 3.5 g TiOSO₄, then adding NaOH to increase the pH ˜8.8.Next, 5 g preformed silica A was added and refluxed at 100° C. for 1 hr.The mixture was filtered hot, washed with ˜500 mL water and ˜20 mLethanol and dried at room temperature. It was then dispersed in ˜800 mLwater and the pH of the solution (typically in alkaline region ˜9) wasadjusted to ˜4 with dilute HNO₃ or acetic acid and stirred at roomtemperature for ˜1 hr. It was then filtered again with ˜2 L of water and˜20 mL ethanol and dried at room temperature. Next, 5 mL CrOAc/MeOHsolution was added (incipient wetness impregnation), followed by dryingat room temperature and activating at 650° C. for 3 hr. This procedurewas repeated by adding organic acids or bases at the organic/titaniummolar ratio shown in Table 16, and the organic was tetraethylammoniumhydroxide for Example 132, diethylamine for Example 133, ethanolaminefor Example 134, triethanolamine for Example 135, ethylamine for Example136, N-methyldiethanol amine for Example 137, acetamide for Example 138,glycolic acid for Example 139, glycine for Example 140, ethylenecarbonate for Example 141, DMF for Example 142, oxalic acid for Example143, before adjusting pH with NaOH represented in the form of the Na/Timolar ratios presented in Table 16. Beneficially, these examplesdemonstrate that various sources of nitrogen can be utilized and veryhigh polymer HLMI values can be obtained.

Note that for Examples 131 and 141-143, sodium was further removed fromthe filtered support or after the heating step by dispersing the supportin a solution of dilute nitric acid at a pH of ˜-3-4 and stirring for30-60 min. For Examples 138-139, sodium was further removed from thefiltered support or after the heating step by dispersing the support inacetic acid at a pH of ˜3-4 and stirring for 30-60 min.

TABLE 16 Org/ Na/ Ti Prod. Activity Activated Catalyst (wt. %) Ex pH TiTi wt % (g/g) (g/g/h) HLMI I₁₀ MI Ti Na Cr 131 8.8 0 8.88 3.5 3153 31414.1 0.6 0 2.96 0.03 1.14 132 9.7 7.7 1.70 2 3014 3690 37.4 8 0.48 2.160.51 1.07 133 10 9.1 1.92 3.5 3185 4662 49.1 10.9 0.65 2.89 0.41 0.97134 9.3 9.8 1.92 3.5 3134 4688 46.4 9.8 0.59 3.71 0.25 1.02 135 13.42.03 3.5 3247 4383 41.4 8.6 0.51 4.01 0.09 1.04 136 10.2 9.5 1.92 3.53000 4435 45.2 9.5 0.56 3.52 0.38 1.04 137 8.3 10.7 1.64 3.5 3141 539325.7 4.8 0.22 3.56 0.03 1.04 138 8.3 1.37 2.63 3.5 3242 4615 20.6 4.00.16 139 8.0 2.72 5.21 3.5 3235 5212 37.2 7.6 0.41 2.01 0.25 1.07 1408.4 3.06 8.39 3.5 3053 2521 32.1 7.1 0.45 2.47 1.38 1.19 141 8.9 3.078.80 3.5 3328 2877 29.3 5.9 0.34 2.41 0.65 1.23 142 8.3 3.7 8.52 3.53137 3941 22.4 4.4 0.19 3.99 0.33 1.12 143 8.2 2.28 13.35 3.5 3190 301429.4 6.1 0.32 3.58 0.51 1.00

Examples 144-157

Examples 144-157 were performed with various inorganic ammonium saltssuch as NH₄Cl, (NH₄)₂SO₄, and (NH₄)₂CO₃, as summarized in Table 17.First, 20 g H₂O was mixed with H₂O₂ and different Ti sources (titaniumisopropoxide for Example 147, potassium titanyl oxalate for Example 148,ammonium titanyl oxalate for Example 149, the other examples usedTiOSO₄), followed by addition of NaOH and ammonium salts to adjust thepH to the value listed in Table 17. Then, 5 g of preformed silica A wasadded and refluxed at 100° C. for 1 hr. The support was filtered, washedmultiple times with water and chromium(III) acetate in methanol wasadded and dried at room temperature. For Examples 150-154, sodium wasfurther removed from the filtered support or after the heating step bydispersing the support in a solution of dilute acid (nitric or acetic)at a pH of ˜3-4 and stirring for 30-60 min. Activation was carried outat 650° C. for a period of 3 hr and the polymerization results arelisted in Table 17. Interestingly, in the absence of either sodium salts(Example 157) or ammonium salts (Example 151), the HLMI potential of thecatalyst was below 6. Manipulating the concentration of both theammonium salts and sodium salts yielded catalysts with very high HLMIpotential (HLMI values of 30-50).

TABLE 17 (NH₄)⁺ (NH₄)⁺/ Na/ Ti Prod. Activity Ex pH source Ti Ti wt %(g/g) (g/g/h) HLMI I₁₀ MI 144 8.8 NH₄Cl 4.8 12.01 2.0 3101 2311 32.0 6.80.41 145 9.0 (NH₄)₂SO₄ 19.2 12.01 2.0 3035 2093 41.0 8.8 0.54 146A 8.4(NH₄)₂SO₄ 4.8 9.6 2.0 3054 1600 31.5 6.9 0.44 146B 9.1 (NH₄)₂SO₄ 4.939.89 3.5 3123 1874 29.1 6.4 0.42 147 9.1 (NH₄)₂SO₄ 10.96 2.88 3.5 30603060 50.6 10.8 0.73 148 8.9 (NH₄)₂SO₄ 10.96 4.82 3.5 3142 1953 48.8 10.70.73 149 7.8 (NH₄)₂SO₄ 4.8 3.22 2.0 3004 4344 41.9 9.0 0.59 150 9.3(NH₄)₂SO₄ 5.48 10.66 3.14 3026 3830 20.6 3.9 0.20 151 8.8 None 0 9.873.14 3153 3141 4.1 0.6 — 152 4.5 (NH₄)₂SO₄ 4.87 8.29 3.14 3117 3620 16.33.1 0.13 153 8.7 (NH₄)₂SO₄ 19.50 10.66 3.14 3166 4166 49.8 10.7 0.64 1548.3 (NH₄)₂SO₄ 85.3 10.36 3.14 3224 4390 22.5 4.4 0.22 155 ~9 (NH₄)₂CO₃12.18 1.07 2.0 3118 4006 27.8 5.8 0.31 156 8.5 (NH₄)₂CO₃ 24.37 1.83 3.143227 4314 38.0 8.1 0.47 157 4.1 (NH₄)₂CO₃ 8.53 0 3.14 3143 2979 3.0 0.3— Activated Catalyst (wt. %) Ex Ti Na Cr 144 2.35 0.58 0.98 150 4.060.03 0.93 151 2.96 0.03 1.14 152 153 3.67 0.14 0.98 154 3.66 0.04 0.87155 2.19 0.08 0.89 156 3.19 0.11 0.87

Examples 158-195

The titanated supports of Examples 158-195 were prepared using a widevariety of reaction times, temperatures, concentrations, pH values, andingredients for the aqueous deposition of titanium onto silica. Ascompared to previous examples, many of Examples 158-195 were performedwithout a nitrogen-containing compound and at a lower pH. Table 18summarizes the results of Examples 158-195 and ICP analysis of certainpre-catalysts and (activated) catalysts (in wt. %).

Example 158: To 50 mL of deionized water was added 25.12 g of a 15%TiOSO₄ solution (which included sulfuric acid to maintain stability) fora target Ti loading of 5.0 wt. %. Next, 11.0 g Na₂SO₄, and 66 mL of an8.17% solution of NaOH was added, yielding a total Na/Ti molar ratio of13.16. Then 20.0 g of silica (500 m²/g, 1.6 mL/g, avg size 100 μm) wereadded and the slurry, now with a pH of about 3, was heated to 75° C. andheld at that temperature with stirring for 15 hr. To wash the sodiumout, 4 L of water was added and the slurry was stirred for 1 hr. Thesolids were filtered out, and approximately 20 mL was added of amethanol solution of chromium (III) acetate containing 0.01 g Cr per mL.The pre-catalyst was dried in a vacuum oven at 100° C. for several hoursand then pushed through a 35-mesh screen. Finally, a 10 g portion ofthis green powder was calcined in dry air at 650° C. for 3 hr.

Example 159: The process of Example 158 was repeated, except that noheat was applied, only stirring at 25° C. for 3 days. 100 mL of waterwas used, and 82 mL of a 2.26 N NaOH stock solution was added instead(7.39 NaOH/Ti, 14.83 total Na/Ti, and pH of ˜4.5). Again, the Ti loadingtarget was 5.0 wt. %.

Example 160: A process similar to Example 158 was used. 15.57 g of 15%TiOSO₄ solution was added (for a Ti target loading of 3.47 wt. %) to 100mL of water. Also added was 21.14 g of the same silica used in Example158, 10.11 g of a 30% H₂O₂ solution, and 11.14 g Na₂SO₄. This yielded adeep orange-red, almost black, solution, indicating a peroxo-Ti complex.The color lightened to orange-yellow when 39 mL of a 2.26 NaOH stocksolution was added. Thus, the total Na/Ti molar ratio in the slurry was16.7. The slurry, which had a pH of about 3.5, was then stirred for 15hr at 25° C. At this point the yellow color had adsorbed onto thesilica. When the stirrer was temporarily halted, the silica settled tothe bottom of the beaker. It had a yellow color, and the solution abovewas clear and colorless, which shows that the peroxo-Ti complex hadadsorbed from the water solution onto the silica. At this point the pHwas about 2.5. The slurry was then stirred and heated to 85° C. for 2hr. Afterward it was diluted with 4 L of additional water to wash sodiumout. After 30 min of stirring, the slurry was filtered, leaving yellowsolids on the filter, and a clear solution that went through the filter.This colorless solution was then acidified by adding 3 mL ofconcentrated H₂SO₄ to it, bringing the pH to about 1, and 5 mL of 30%H₂O₂ was added. This combination (acid and H₂O₂) would have given a deeporange color had any titanium passed through the filter. But instead, nochange in color was observed. The solution was still colorless, provingthat all of the Ti had indeed adsorbed onto the silica. Finally, thefilter cake was impregnated with Cr, dried, screened, and calcined asindicated above in Example 158.

Example 161: A procedure similar to that in Example 158 was again used.Into 199 mL of water was added 16.06 g of 15% TiOSO₄ solution, 7.76 g ofarginine alpha-ketogutarate (AKG), and 5 mL of 30% H₂O₂. Afterdissolution, 9.21 g of Na₂CO₃ was added to raise the pH to about 9.5,and 20.2 g was added of the same silica used above in Example 158. Themixture was heated with stirring at 90° C. for 7 hr. It was then allowedto stir for 3 days at room temperature. At first, during the heattreatment, the yellow color adsorbed onto the silica, as described inExample 160. When the stirring was temporarily stopped, the yellowsilica settled to the bottom leaving a clear colorless solution above.After 7 hours of stirring at 90° C., however, the yellow color haddisappeared, indicating that the H₂O₂ had decomposed in contact with theAKG. The support was then filtered and the liquid passing through thefilter was tested for the presence of Ti, as indicated above withadditional H₂O₂ and H₂SO₄. No color developed in the solution,indicating that no trace of Ti was found in the liquid, and thereforethat all the Ti still remained adsorbed on the silica. The support waswashed in 4 L of water which had been acidified to a pH ˜4 with aceticacid, followed by another filtration. This was done to enhance sodiumremoval. After the second filtration, the semi-dry support wasimpregnated with Cr, dried, screened, and calcined, all as described inExample 158.

Example 162: To 200 mL of water was added 15.39 g of 15% TiOSO₄ solutionand 5 mL of 30% H₂O₂, which made a deep orange solution. Sodiumbicarbonate, 6.05 g, was added to bring the original pH-2 up to pH-4,and the orange solution turned to yellow. The same silica used above,20.8 g, was then added, along with 4 mL of ethylamine, and the slurrywas heated to 92° C. for 4 hr. The pH after heating was about 6.5. Theslurry was filtered, and the liquid was again tested for Ti as describedabove, but none was found. The solid support was washed and filtered twotimes using 1 L of acidified water, e.g. 2 mL of acetic acid had beenadded, to remove sodium. The final support was impregnated with Cr,dried, screened, and calcined exactly as described above in Example 158.

Example 163: A procedure similar to that in Example 158 was again used.Into 96.06 mL of water was added 1.1969 g of TiOSO₄ powder, along with3.0 mL of 30% H₂O₂ and 2.01 g of Na₂SO₄ to make a deep orange solution.Then 6.5 mL of 2.26 N NaOH stock solution was added to bring the pH upto 3.6, yielding a total molar Na/Ti ratio of 5.9. 20.02 g of silica wasadded, the same silica used in the experiments above. After 1 hr ofstirring at room temperature, the yellow color was totally adsorbed ontothe silica, as was evident because the yellow color settled out with thesilica when the stirring was temporarily stopped, leaving a colorlesssolution above the settled yellow solid. The slurry was then heated withstirring to 80-85° C. for 2 hr. The final pH was 6.0. The slurry wasfiltered leaving a yellow solid on the filter and the clear colorlessliquid passing through the filter. This liquid was acidified with H₂SO₄and 2 mL of 30% H₂O₂ added, but it still did not display any color,confirming that all of the Ti had indeed adsorbed quantitatively ontothe silica. The solid was then impregnated with Cr, dried, screened andcalcined as described in Example 158.

Example 164: The procedure described in Example 163 was repeated, butwith these changes: 105 mL water, 1.52 g Na₂SO₄ and 9.7 mL of NaOHsolution, yielding a total Na/Ti molar ratio of 8.9 and a pH of 7.7 (8.3after heating). The slurry was heated at 80° C. for 4 hr. Again, theyellow color from the peroxo-Ti complex completely adsorbed onto thesilica, as indicated by settling, and later by testing the filteredcolorless water with H₂SO₄ and H₂O₂.

Example 165: The procedure described in Example 163 was repeated, butwith these changes: No NaOH, 2.98 g Na₂SO₄, pH 1.9, molar Na/Ti 5.6.

Example 166: Into 96.6 mL of deionized water was added 1.17 g of TiOSO₄powder, 3.03 g Na₂SO₄, 3 mL of 35% H₂O₂, and 8.51 mL of 1.37 N NH₄OHsolution. This produced a yellow solution of pH 3.5. 20.1 g of silica(same grade as above) was added, and the yellow color adsorbed ontosilica with a few minutes of stirring at 25° C. The slurry was allowedto stir for 3 days at 25° C., then filtered producing a yellow solid onthe filter and a clear colorless liquid passing through the filter. Theliquid was tested for Ti in the usual manner, but no Ti was detected,indicating that all of it had adsorbed onto the silica. The solid waswashed in 2 L of water, which was stirred for 30 min, producing a pH of5. The solid was filtered out again, and then finished as describedabove, that is, Cr impregnation, drying, screening, and calcination.

Example 167: Into 98.8 mL of deionized water was added 1.167 g of TiOSO₄powder, 3 mL of 35% H₂O₂, and 8 mL of 1.37 N NH₄OH solution. Thisproduced a yellow solution of pH 3.7. 20.0 g of silica (same grade asabove) was added, and the yellow color adsorbed onto silica with a fewmin of stirring at 25° C. The slurry was allowed to stir for 2 hr at 98°C., then filtered producing a yellow solid on the filter and a clearcolorless liquid passing through the filter. The liquid was tested forTi in the usual manner, but no Ti was detected, indicating that all ofit had adsorbed onto the silica. The solid was washed in 2 L of water,which was stirred for 1 hr. The solid was filtered out again, and thenfinished as described above, that is, Cr impregnation, drying,screening, and calcination.

Example 168: Into 87.35 mL of deionized water was added 1.20 g of TiOSO₄powder, 3 mL of 35% H₂O₂, and 10 mL of Mg(OH)₂ slurry (1.33 M). Thisproduced a clear yellow solution of pH 4.1. 20.0 g of silica (same gradeas above) was added, and after being stirred for 2 hr at 25° C., theyellow color adsorbed onto silica. That is, the yellow color settled outwith the silica when the stirring was stopped, leaving a clear liquidabove. The slurry was allowed to stir for 15 hr at 25° C., then it wasfiltered producing a yellow solid on the filter and a clear colorlessliquid passing through the filter. The liquid was tested for Ti in theusual manner, but no Ti was detected, indicating that all of it hadadsorbed onto the silica. The solid was washed in 2 L of water, whichwas stirred for 1 hr giving a pH of about 5. The solid was filtered outagain, and then finished as described above, that is, Cr impregnation,drying, screening, and calcination.

Example 169: Into 108.5 mL of deionized water was added 15.6 g of 15%TiOSO₄ solution, 3 mL of 35% H₂O₂, 13.83 g Na₂SO₄, 20.25 g of MgSO₄, and50.0 mL of 2.26 N NaOH solution. This produced a clear yellow solutionof pH 4.3. This resulted in a Na/Ti molar ratio of 21.3 and a Mg/Timolar ratio of 11.5. Then 20.1 g of silica (same grade as above) wasadded, and the slurry was heated to 92° C. for 45 min. Upon settling,the yellow color adsorbed onto silica, leaving a clear colorless liquidabove of pH 6.2. The slurry was filtered producing a yellow solid on thefilter and a clear colorless liquid passing through the filter. Theliquid was tested for Ti in the usual manner, but no Ti was detected,indicating that all of it had adsorbed onto the silica. 2 L of water, towhich 5 mL of acetic acid had been added to reach pH 3.7, was then addedand the slurry stirred for 30 min to remove sodium. The solid wasfiltered out again, and then finished as described above, that is, Crimpregnation, drying, screening, and calcination.

Example 170: Into 92.3 mL of deionized water was added 15.43 g of 15%TiOSO₄ solution, 3 mL of 35% H₂O₂, 14.8 g of MgSO₄, and 30.32 mL of 1.33M Mg(OH)₂ slurry. This produced a clear yellow solution of pH 4.2 andhaving a Mg/Ti molar ratio of 11.2. Then 20.1 g of silica (same grade asabove) was added, and the slurry was heated to 80° C. for 5 hr. Uponsettling, the yellow color adsorbed onto silica, leaving a clearcolorless liquid above of pH 5.8. The slurry was filtered producing ayellow solid on the filter and a clear colorless liquid passing throughthe filter. The liquid was tested for Ti in the usual manner, but no Tiwas detected, indicating that all of it had adsorbed onto the silica.The solid was washed and filtered twice in 2 L of water, to which 3 mLof acetic acid had been added to reach pH 3.8. In each wash the slurrywas stirred for 30 min to remove metal ions. The solid was then finishedas described above, that is, Cr impregnation, drying, screening, andcalcination.

Example 171: The procedure described in Example 164 was repeated, butwith these changes: 100 mL water, 1.237 g TiOSO₄ powder, 8.56 g Na₂SO₄and 9.7 mL of NaOH solution, yielding a total Na/Ti molar ratio of 9.8.The slurry was heated at 93° C. for 2.5 hr. The yellow color from theperoxo-Ti complex completely adsorbed onto the silica, as indicated bysettling, and later by testing the filtered colorless water with H₂SO₄and H₂O₂. The slurry was filtered, leaving a yellow solid on the filterwhile a colorless clear liquid went through the filter. This liquid wasacidified with 2 mL concentrated H₂SO₄ and then 2 mL H₂O₂. This producedno color, indicating that all of the Ti had adsorbed onto the silica.The solid was washed in 2 L of water, then finished as indicated above,that is, Cr impregnation, drying, screening, and calcining at 650° C.

Example 172: In this preparation 2.417 g of TiOSO₄ powder was dissolvedin 229.3 mL of de-ionized water, as well as 6 mL of 35% H₂O₂, 6.5 mL of2.26 N NaOH stock solution, and 4.045 g of Na₂SO₄. This resulted in a4.9 Na/Ti molar ratio. Silica, 40.0 g of the same grade used above, wasthen added and the mixture stirred for 4 hr. The yellow color was fullyadsorbed onto the silica; when the stirring was temporarily halted, theyellow-colored silica quickly settled out leaving clear colorlesssolution above. This slurry was then split in half. The first half wasfiltered without washing and then dried in a vacuum oven at 100° C.overnight. The liquid that passed through the filter was acidified withH₂SO₄ and then 3 mL of H₂O₂ was added, as a test for Ti. There was nocolor change, indicating that all of the Ti had been adsorbed onto thesilica. The dried silica was then washed in 2 L of water containing 3 mLof acetic acid so that the pH was about 3.5. After 30 min of stirring at25° C., the silica was again filtered out, and finished as described inExample 158, that is, impregnated with Cr, dried, screened, and calcinedat 650° C. The purpose of the additional drying step was to determinethe impact of a hydrothermal treatment in the presence of sodium.

Example 173: In this preparation the other half of the slurry made inExample 172 was heated at 95° C. for 2.5 hr. Then it was filtered andwashed with 2 L of water containing 3 mL acetic acid. It was finished inthe manner of Example 158 (Cr, dry, screen, calcine).

Example 174: To test the effect of very high sodium levels, in thispreparation 123.4 mL of water was weighed into a beaker, into which wasadded 15.63 g of 15% TiOSO₄, 3 mL of 35% H₂O₂, 30.66 g Na₂SO₄, and 50 mLof 2.26 N NaOH solution. This resulted in a Na/Ti molar ratio of 37.4.20.0 g was added of the same silica as used above. As the NaOH wasslowly added, the color of the solution changed from deep orange-red toa light yellow as the pH rose to 4.5. It was then heated at 93° C. for1.5 hr, resulting in a pH of 6.3. The support was washed in 1 L ofwater, then filtered and finished in the same manner as Example 158.

Example 175: To determine the impact of heat treatment, in thispreparation 129.9 mL of water was weighed into a beaker, into which wasadded 17.31 g of 15% TiOSO₄, 3 mL of 35% H₂O₂, 30.76 g Na₂SO₄, and 54.5mL of 2.26 N NaOH solution. This resulted in a Na/Ti molar ratio of36.5. 20.9 g was added of the same silica as used above. As the NaOH wasslowly added, the color of the solution changed from deep orange-red toa light yellow as the pH rose to 4.5. It was then stirred at 25° C. for15 hr. Afterward, 2 L of water was added, producing a pH of 5.5, and thesupport was stirred for 30 min to wash out sodium ions. Then it wasfiltered and finished in the same manner as Example 158.

Example 176: Once adsorbed onto the silica, the H₂O₂ chelated to the Tican be reduced by the addition of reducing agents, to determine if thisenhances the deposition and attachment of Ti onto the silica surface.Thus, in this experiment, 125 mL of water was poured into a beaker,followed by 16.59 g of 15% TiOSO₄ solution, 3 mL 35% H₂O₂ solution,29.76 g Na₂SO₄, 20.0 g of silica (described above) and 53 mL of 2.26 NNaOH stock solution. The slurry was stirred for 30 min to allow theperoxo-Ti complex to adsorb onto the silica. The final pH was 4.3. Next9.46 g of NaHSO₃ was added. The pH dropped back to 2.9, which shouldbring back a deep orange color, but instead it turned the yellow verypale, almost white. Then the heat was turned on, and before thetemperature could rise to 66° C., the yellow color had completelyvanished. Nevertheless, heating was continued to 90° C. where itremained for 1 hr. The support was then washed in 2 L of water, andfinished in the same way as in Example 158 (Cr, dry, screen, calcine).

Example 177: In another experiment 61.5 g of 15% TiOSO₄ was added to364.4 mL of water in a beaker, along with 12 mL of 35% H₂O₂ and 92.95 gof Na₂SO₄. Then 80.4 g of the same silica grade described above wasadded, followed by a slow addition of 194 mL of 2.26 N NaOH stocksolution. The final mixture, which had a pH of 4.1 was stirred at 25° C.for 15 hr. The next day it was noticed that when the stirrer wastemporarily turned off the yellow color settled out with the silica,indicating that the peroxo-Ti complex had been adsorbed. The slurry wasthen split into two parts. One part was then heated to 95° C. for 3 hrresulting in a pH of 5.7. Then this part was split into two parts again.To the first part was added 9.0 g of (NH₄)₂SO₄ and then the temperaturewas raised again to 95° C. for 2 hr. The color remained yellow. This wasdone to determine the impact of whether the NH₄ ion was present duringthe adsorption or could be added after adsorption to enhance theperformance of the catalyst. This part of the slurry was then finishedin the usual way. It was washed and filtered twice in 2 L of water. Eachtime the filter retained the yellow color, while a clear colorlesssolution pass through. When tested, this clear solution was not found tocontain Ti. Next 20 mL of a chromium acetate in methanol solution (0.01g Cr/mL) was added to the filtered solids, the mixture was dried in avacuum oven at 100° C. for several hr, then it was pushed through a35-mesh screen, followed by calcination in dry air at 650° C. for threehr.

Example 178: In the second part from Example 177, 4.43 g of NaHSO₃ wasadded to the slurry at 25° C. There was no color change within 30 min.Therefore, the slurry was heated to 85° C., and then it graduallychanged color from yellow to white, indicating reduction of H₂O₂ ligandson the Ti. It was heated for 2 hr and the slurry was filtered and theclear liquid passing through the filter was again found to contain no Tiin the standard test. The filtered solids were stirred into 2 L of waterfor 30 min at pH 5.2. The solids were washed and filtered a second timein 2 L of water. Next 20 mL of a chromium acetate in methanol solution(0.01 g Cr/mL) was added to the filtered solids, the mixture was driedin a vacuum oven at 100° C. for several hr, then it was pushed through a35-mesh screen, followed by calcination in dry air at 650° C. for threehr.

Example 179: The second half described in Example 177, 11.47 g of Na₂CO₃was added to test the effect of pH, which rose to 10.1. This half wasalso split into two equal parts. In the first part, the slurry wasstirred at 25° C. for 30 min, and then washed in 2 L of water containing3 mL of acetic acid (pH 5.3). After 30 min of stirring it was filtered,and then washed again in 1 L of water and filtered again. The solids onthe filter were impregnated with 20 mL of 0.01 g/mL methanolic chromium(III) acetate solution, dried in a vacuum oven at 100° C. overnight,then pushed through a 35 mesh screen, and finally calcined for 3 hr indry air at 650° C.

Example 180: In the second part from Example 179, which is the secondhalf from Example 177, the slurry was heated to 87° C. for 2 hr. Theyellow solids were then filtered, washed, and filtered again 2 timeseach in 2 L of water. Next 20 mL of a chromium acetate in methanolsolution (0.01 g Cr/mL) was added to the filtered solids, the mixturewas dried in a vacuum oven at 100° C. for several hr, then it was pushedthrough a 35-mesh screen, followed by calcination in dry air at 650° C.for three hr.

Example 181: This test was designed to adsorb Ti in the absence ofsodium, but then to conduct the hydrothermal treatment in the presenceof sodium. Thus, into 111.11 g of de-ionized water was dissolved 2.29 gof TiOSO₄ powder, 3 mL of 35% H₂O₂ solution, and 14.54 g of 1.37 N NH₄OHstock solution. As the NH₄OH was added the deep orange-red startingcolor faded to a lighter orange color, and the pH rose to 3.0. Thesilica, 20.2 g of the same grade used in Example 158, was added next.The slurry was stirred at 25° C. for 15 hr to allow for adsorption.After this treatment, the yellow color was adsorbed onto the silica.When the stirring was temporarily halted the yellow silica settledleaving a clear colorless solution above. At this point 30.2 g of Na₂SO₄was added (28.0 Na/Ti molar ratio) and the temperature was raised to 85°C. for 4 hr. The silica was then filtered off, washed for 30 min in 2 Lof water, filtered again, impregnated with 20 mL of chromiumacetate/methanol solution (0.01 g Cr/mL), dried in a vacuum oven at 100°C. for several hr, pushed through a 35-mesh screen, and then calcined indry air at 650° C. for 3 hr.

Example 182: This test was designed to reverse the process of Example181. That is, Ti was adsorbed in the presence of sodium, buthydrothermally treated in the absence of sodium. Thus, into 116.09 g ofde-ionized water was dissolved 2.34 g of TiOSO₄ powder, 3 mL of 35% H₂O₂solution, 30.39 g of Na₂SO₄, and 12.6 mL of 2.26 N NaOH stock solution.As the NaOH was slowly added the deep orange-red color changed to alight yellow-orange color, and the pH rose to 4.2. Silica, 20.03 g ofthe same grade used in Example 158, was added. The slurry was stirred at25° C. for 15 hr. After this treatment, the yellow color was adsorbedonto the silica. When the stirring was temporarily halted the yellowsilica settled leaving a clear colorless solution above. At this pointthe yellow silica was filtered, and the clear colorless liquid passingthrough the filter was tested for the presence of any Ti. It wasacidified by the addition of 3 mL concentrated H₂SO₄, then 5 mL 35% H₂O₂solution was added, but there was no change to an orange color,indicating the absence of Ti in the solution. The yellow filtered silicawas then washed in 2 L of water and filtered again two times. Then theyellow silica was slurried in 200 mL of de-ionized water and heated to90° C. for 1.5 hr. It was subsequently filtered again, impregnated with20 mL of chromium acetate/methanol solution (0.01 g Cr/mL), dried in avacuum oven at 100° C. for several hr, pushed through a 35-mesh screen,and then calcined in dry air at 650° C. for 3 hr.

Example 183: This experiment was designed to test extremely high levelsof sodium combined with low hydrothermal temperature. Therefore, into95.36 g de-ionized water was dissolved 15.64 g of 15% TiOSO₄ solution,30.49 g NaNO₃, 29.69 g Na₂SO₄, 3 mL 35% H₂O₂ solution, and 50 mL of 2.26N NaOH stock solution. This resulted in a total Na/Ti molar ratio of60.74. As the NaOH was slowly added the deep orange-red color changed toa light yellow-orange color, and the pH rose to 4.0. Silica, 20.8 g ofthe same grade used in Example 158, was added and the slurry was stirredat 56° C. for 15 hr. After this treatment, the yellow color was adsorbedonto the silica. The stirring was temporarily halted, and the yellowsilica settled out leaving a clear colorless solution above. At thispoint the yellow silica was filtered, and the clear colorless liquidpassing through the filter was tested for the presence of any Ti. It wasacidified by the addition of 3 mL concentrated H₂SO₄, then 5 mL 35% H₂O₂solution was added, but there was no change to an orange color,indicating the absence of Ti in the solution. The yellow filtered silicawas then washed in 2 L of water and filtered again two times. Then theyellow silica was impregnated with 20 mL of chromium acetate/methanolsolution (0.01 g Cr/mL), dried in a vacuum oven at 100° C. for severalhr, pushed through a 35-mesh screen, and then calcined in dry air at650° C. for 3 hr.

Example 184: This experiment was designed to test extremely high levelsof sodium combined with medium hydrothermal temperature. Therefore, into96.68 g de-ionized water was dissolved 16.14 g of 15% TiOSO₄ solution,62.09 g NaNO₃, 40.4 g Na₂SO₄, 3 mL 35% H₂O₂ solution, and 52 mL of 2.26N NaOH stock solution. This resulted in a total Na/Ti molar ratio of93.64. As the NaOH was slowly added the deep orange-red color changed toa light yellow-orange color, and the pH rose to 3.8. Silica, 20.4 g ofthe same grade used in Example 158, was added and the slurry was stirredat 70° C. for 5.5 hr. After this treatment, the yellow color wasadsorbed onto the silica. The stirring was temporarily halted, and theyellow silica settled out leaving a clear colorless solution above. Atthis point the yellow silica was filtered, and the clear colorlessliquid passing through the filter was tested for the presence of any Ti.It was acidified by the addition of 3 mL concentrated H₂SO₄, then 5 mL35% H₂O₂ solution was added, but there was no change to an orange color,indicating the absence of Ti in the solution. The yellow filtered silicawas then washed in 2 L of water and filtered again two times. Then theyellow silica was impregnated with 20 mL of chromium acetate/methanolsolution (0.01 g Cr/mL), dried in a vacuum oven at 100° C. for severalhr, pushed through a 35-mesh screen, and then calcined in dry air at650° C. for 3 hr.

Example 185: This experiment was designed to determine the impact or adifferent alkali metal ion, potassium. Therefore, into 98.9 g de-ionizedwater was dissolved 15.41 g of 15% TiOSO₄ solution, 50.9 g KNO₃, 3 mL35% H₂O₂ solution, and 101.5 mL of 1.31 N KOH stock solution. Thisresulted in a total K/Ti molar ratio of 44.08. As the KOH was slowlyadded the deep orange-red color changed to a light yellow-orange color,and the pH rose to 3.5. Silica, 20.1 g of the same grade used in Example158, was added and the slurry was stirred at 90° C. for 1.5 hr. Afterthis treatment, the yellow color was adsorbed onto the silica. Thestirring was temporarily halted, and the yellow silica settled outleaving a clear colorless solution above. At this point the yellowsilica was filtered, and the clear colorless liquid passing through thefilter was tested for the presence of any Ti. It was acidified by theaddition of 3 mL concentrated H₂SO₄, then 5 mL 35% H₂O₂ solution wasadded, but there was no change to an orange color, indicating theabsence of Ti in the solution. The yellow filtered silica was thenwashed in 2 L of water and filtered again two times. Then the yellowsilica was impregnated with 20 mL of chromium acetate/methanol solution(0.01 g Cr/mL), dried in a vacuum oven at 100° C. for several hr, pushedthrough a 35-mesh screen, and then calcined in dry air at 650° C. for 3hr.

Example 186: This experiment was designed to determine the effect of Tiadsorption from a very dilute Ti solution. Therefore, into 624.61 gde-ionized water was dissolved 15.43 g of 15% TiOSO₄ solution, 3 mL 35%H₂O₂ solution, 179.94 g Na₂SO₄, and 35.1 mL of 2.80 N NaOH stocksolution. This resulted in a total Na/Ti molar ratio of 177.6. Althoughhigh, this ratio produces the same molar Na concentration (6.5 M) thatwas used in Example 185 and earlier experiments. As the NaOH was slowlyadded the deep orange-red color changed to a light yellow-orange color,and the pH rose to 3.6. Silica, 20.5 g of the same grade used in Example158, was added and the slurry was stirred at 83° C. for 2 hr. After thistreatment, the yellow color was indeed adsorbed onto the silica. Thestirring was temporarily halted and the yellow silica settled outleaving a clear colorless solution above. At this point the yellowsilica was filtered, and the clear colorless liquid passing through thefilter was tested for the presence of any Ti. It was acidified by theaddition of 3 mL concentrated H₂SO₄, then 5 mL 35% H₂O₂ solution wasadded, but there was no change to an orange color, indicating theabsence of Ti in the solution. The yellow filtered silica was thenwashed in 2 L of water and filtered again two times. Then the yellowsilica was impregnated with 20 mL of chromium acetate/methanol solution(0.01 g Cr/mL), dried in a vacuum oven at 100° C. for several hr, pushedthrough a 35-mesh screen, and then calcined in dry air at 650° C. for 3hr.

Example 187: This experiment was designed to test the effect of Tideposition from a high Ti concentration at low pH. Therefore, into 50.1g de-ionized water was dissolved 15.43 g of 15% TiOSO₄ solution, 24.0 gNaNO₃, 3 mL 35% H₂O₂ solution. This resulted in a total Na/Ti molarratio of 19.5 and a pH of less than 1. Silica, 20.0 g of the same gradeused in Example 158, was added and the slurry was stirred at 88° C. for4 hr. No yellow color remained. The silica was then filtered, washed in2 L of water and filtered again two times. Then the silica wasimpregnated with 20 mL of chromium acetate/methanol solution (0.01 gCr/mL), dried in a vacuum oven at 100° C. for several hr, pushed througha 35-mesh screen, and then calcined in dry air at 650° C. for 3 hr.

Example 188: This experiment was designed to test the effect of Tideposition from a high Ti concentration. Therefore, into only 15.0 mL ofde-ionized water was dissolved 15.43 g of 15% TiOSO₄ solution, 24.02 gNaNO₃, 3 mL 35% H₂O₂ solution, and 39.1 mL of 2.80 N NaOH stocksolution. This resulted in a total Na/Ti molar ratio of 27.0. As theNaOH was slowly added the deep orange-red color changed to a lightyellow-orange color, and the pH rose to 4.7. Silica, 20.1 g of the samegrade used in Example 158, was added and the slurry was stirred at 88°C. for 2 hr. After this treatment, the yellow color was indeed adsorbedonto the silica. The stirring was temporarily halted, and the yellowsilica settled out leaving a clear colorless solution above. At thispoint the yellow silica was filtered, and the clear colorless liquidpassing through the filter was tested for the presence of any Ti. It wasacidified by the addition of 3 mL concentrated H₂SO₄, then 5 mL 35% H₂O₂solution was added, but there was no change to an orange color,indicating the absence of Ti in the solution. The yellow filtered silicawas then washed in 2 L of water and filtered again two times. Then theyellow silica was impregnated with 20 mL of chromium acetate/methanolsolution (0.01 g Cr/mL), dried in a vacuum oven at 100° C. for severalhr, pushed through a 35-mesh screen, and then calcined in dry air at650° C. for 3 hr.

Example 189: This experiment was designed to test the effect of highlevels of Ti deposition. Therefore, into 63.24 g of de-ionized water wasdissolved 67.0 g of 15% TiOSO₄ solution, and 3 mL 35% H₂O₂ solution toproduce a deep red, nearly black, solution. Then 18.38 g of Na₂CO₃ wasslowly added which produced a pH of 3.3. This resulted in a total Na/Timolar ratio of 5.5. As the Na₂CO₃ was slowly added the deep red-blackcolor changed to a lighter yellow-orange color, and the pH rose to 3.3.Silica, 20.1 g of the same grade used in Example 158, was added and theslurry was stirred at 85° C. for 1.5 hr. The yellow filtered silica wasthen washed in 2 L of water and filtered again two times. Then theyellow silica was impregnated with 20 mL of chromium acetate/methanolsolution (0.01 g Cr/mL), dried in a vacuum oven at 100° C. for severalhr, pushed through a 35-mesh screen, and then calcined in dry air at650° C. for 3 hr.

Example 190: This experiment was designed to test the effect of highlevels of Ti deposition from the basic side. Therefore, into 144.2 g ofde-ionized water was dissolved 31.37 g of Na₂CO₃ and 3 mL 35% H₂O₂solution, followed by 44.61 g of 15% TiOSO₄ solution, to produce ayellow solution of pH 8.3. This resulted in a total Na/Ti molar ratio of14.1. Silica, 20.1 g of the same grade used in Example 158, was addedand the slurry was stirred at 80° C. for 3 hr. The yellow silica wasfiltered and washed in 2 L of water and filtered again two times. Witheach wash, however, the pH of the wash water was measured at 9.5.Knowing that sodium is difficult to remove at this pH, another wash wasconducted in which 2 L of water was acidified with 5 mL of acetic acidto pH 3.5. The slurry was stirred for 30 min and then filtered again.Then the yellow silica was impregnated with 20 mL of chromiumacetate/methanol solution (0.01 g Cr/mL), dried in a vacuum oven at 100°C. for several hr, pushed through a 35-mesh screen, and then calcined indry air at 650° C. for 3 hr.

Example 191: This experiment was designed to test the effect of Tideposition at neutral pH from the basic side. Therefore, into 99.6 g ofde-ionized water was dissolved 8.80 g of 15% TiOSO₄ solution, 4 mL of35% H₂O₂ solution, and 68.4 mL of 1.00 N NaOH. This produced a clearyellow solution. Next 12.02 g of NaNO₃ was added, giving a pH of 6.2,and causing precipitation. However, precipitation does not necessarilystop Ti deposition on the silica, which suggests that the Ti precipitatemay still be partially soluble and therefore mobile in the solution.This produced a total Na/Ti molar ratio of 25.4. Next the silica, 20.1 gof the same grade used in Example 158, was added and the slurry wasstirred at 90° C. for 1.5 hr. The silica was filtered and washed in 2 Lof water and filtered again two times. Then the silica was impregnatedwith 20 mL of chromium acetate/methanol solution (0.01 g Cr/mL), driedin a vacuum oven at 100° C. for several hr, pushed through a 35-meshscreen, and then calcined in dry air at 650° C. for 3 hr.

Example 192: This experiment was designed to test the effect of limitingthe H₂O₂ concentration to 1 H₂O₂/Ti on the deposition of Ti. Therefore,into 94.5 g of de-ionized water was dissolved 15.5 g of 15% TiOSO₄solution, 0.5 mL of 35% H₂O₂ solution (H₂O₂/Ti of 1), and 37.0 mL of2.80 N NaOH stock solution. This produced a clear yellow solution havinga pH of 4.4. This produced a total Na/Ti molar ratio of 7.1. Next thesilica, 20.4 g of the same grade used in Example 158, was added and theslurry was stirred at 90° C. for 5 hr. The silica was filtered andwashed in 2 L of water and filtered again two times. Then the silica wasimpregnated with 20 mL of chromium acetate/methanol solution (0.01 gCr/mL), dried in a vacuum oven at 100° C. for several hr, pushed througha 35-mesh screen, and then calcined in dry air at 650° C. for 3 hr.

Example 193 This experiment was designed to determine if Ti could bedeposited in the absence of sodium from the oxalate salt, that is, ifoxalate/Ti is 2. Therefore, into 100.0 g of de-ionized water wasdissolved 3.68 g of oxalic acid dihydrate and 3 mL of 35% H₂O₂ solution.Next 4.43 mL of titanium tetra-isopropoxide was added, which immediatelyhydrolyzed and precipitated hydrous titania. However, with continuedstirring at 25° C. the precipitate dissolved in about 10 min to form adeep orange solution. Next 5.5 g of NH₄Cl was added and over the next 20min 55.1 mL of 1.37 N NH₄OH was dripped into the mixture, resulting inthe pH being measured at 8.1. Lastly the silica, 20.0 g of the samegrade used in Example 158, was added and the slurry was stirred at 90°C. for 1.5 hr. The yellow-orange color was adsorbed onto the silica, butwith continued heating the color changed to white or colorless. Thefinal pH was measured as 7.0. The silica was filtered and washed in 2 Lof water and filtered again two times. Then the silica was impregnatedwith 20 mL of chromium acetate/methanol solution (0.01 g Cr/mL), driedin a vacuum oven at 100° C. for several hr, pushed through a 35-meshscreen, and then calcined in dry air at 650° C. for 3 hr.

Example 194: This experiment was designed to determine if Ti could bedeposited in the absence of sodium from the oxalate salt, that is, ifoxalate/Ti is 1. Therefore, into 100.0 g of de-ionized water wasdissolved 1.84 g of oxalic acid dihydrate and 3 mL of 35% H₂O₂ solution.Next 4.43 mL of titanium tetra-isopropoxide was added, which immediatelyhydrolyzed and precipitated hydrous titania. However, with continuedstirring at 25° C. the precipitate dissolved in about 10 min to form adeep orange solution. Next 5.9 g of NH₄Cl was added and over the next 20min 36.96 mL of 1.37 N NH₄OH was dripped into the mixture, resulting inthe pH being measured at 8.1. Lastly the silica, 20.0 g of the samegrade used in Example 158, was added and the slurry was stirred at 90°C. for 1.5 hr. The yellow-orange color was adsorbed onto the silica, butwith continued heating the color changed to white or colorless. Thefinal pH was measured as 7.0. The silica was filtered and washed in 2 Lof water and filtered again two times. Then the silica was impregnatedwith 20 mL of chromium acetate/methanol solution (0.01 g Cr/mL), driedin a vacuum oven at 100° C. for several hr, pushed through a 35-meshscreen, and then calcined in dry air at 650° C. for 3 hr.

Example 195: This experiment was designed to explore the use of lithiumions in place of the usual sodium ions. Into 100 mL of de-ionized waterwas added 2.52 g of oxalic acid dihydrate, 3 mL of 35% H₂O₂, and 4.4 mLof titanium tetra-isopropoxide. After about 10 min the titanium wentinto solution to make deep orange solution of pH<1. Then 10.9 g of LiNO₃was added. Next 9.49 g of ammonium carbonate was added to raise the pHto 8.7. As the pH increased the color also lightened to yellow. Theslurry was heated to 92° C. where it was heated for 1.5 hr. The silicawas filtered, then washed in 2 L of water and filtered again. Then thesilica was impregnated with 20 mL of chromium acetate/methanol solution(0.01 g Cr/mL), dried in a vacuum oven at 100° C. for several hr, pushedthrough a 35-mesh screen, and then calcined in dry air at 650° C. for 3hr.

TABLE 18 Ti Na/Ti Example Description wt. % molar 158 TiOSO₄ + NaOH +Na₂SO₄, pH 3, 75° C., 15 hr 5.0 13.2 159 TiOSO₄ + NaOH + Na₂SO₄, pH 4,25° C., 3 days 5.0 14.8 160 TiOSO₄ + H₂O₂ + NaOH + Na₂SO₄, pH 3.5, 85°C., 2 hr 3.5 16.7 161 TiOSO₄ + H₂O₂ + NaHCO₃ + AKG, pH 9.5, 90° C. 3.55.8 162 TiOSO₄ + H₂O₂ + NaHCO3 + EtNH₂, pH 4, 92° C., 3 hr 3.5 1.1 163TiOSO₄ + H₂O₂ + NaOH + Na₂SO₄, pH 3.6, 83° C., 2 hr 1.8 5.9 164 TiOSO₄ +H₂O₂ + NaOH + Na₂SO₄, pH 7.7, 80° C., 4 hr 1.8 8.9 165 TiOSO₄ + H₂O₂ +Na₂SO₄, pH 1.9, 85° C., 1 hr 1.8 5.6 166 TiOSO₄ + H₂O₂ + NH₄OH + Na₂SO₄,pH 3.5, 25° C., 3 days 1.8 2.9 167 Ti, TiOSO₄ + H₂O₂ + NH₄OH, pH 3.7,98° C., 2 hr 1.8 0.0 168 TiOSO₄ + H₂O₂ + Mg(OH)₂, pH 4.1, 25° C., 15 hr1.8 1.8 Mg/Ti 169 TiOSO₄ + MgSO4 + H₂O₂ + NaOH + Na₂SO₄, pH 4.3, 92° C.,0.8 hr 3.5 21.3 170 TiOSO₄ + Mg(OH)₂ + MgSO₄ + H₂O₂, pH 4.2, 80° C., 5hr 3.5 11.2 Mg/Ti 171 TiOSO₄ + H₂O₂ + 2.8 NaOH + Na₂SO₄, 93° C., 2.5 hr1.8 18.4 172 TiOSO₄ + H₂O₂ + NaOH + Na₂SO₄, 25° C., 4 hr 1.8 4.9 173TiOSO₄ + H₂O₂ + NaOH + Na₂SO₄, 95° C., 2.5 hr 1.8 4.9 174 TiOSO₄ +H₂O₂ + NaOH + Na₂SO₄, pH 4.5, 93° C., 1.5 hr 3.5 37.4 175 TiOSO₄ +H₂O₂ + NaOH + Na₂SO₄, pH 4.5, 25° C., 15 hr 3.5 36.5 176 TiOSO₄ + H₂O₂ +NaOH + NaHSO₃, pH 4.3, 90° C., 1 hr 3.5 43.2 177 TiOSO₄ + H₂O₂ + Na₂SO₄,95° C., 3 hr, (NH₄)₂SO₄, pH 4.1, 95° C., 2 hr 3.5 29.8 178 TiOSO₄ +H₂O₂ + Na₂SO₄, 95° C., 3 hr, NaHSO₃, pH 4.1, 85° C., 2 hr 3.5 30.4 179TiOSO₄ + H₂O₂ + Na₂SO₄, 95° C., 3 hr, pH 4.1, Na₂CO₃, pH 10, 25° C. 3.533.5 180 TiOSO₄ + H₂O₂ + Na₂SO₄, 95° C., 3 hr, pH 4.1, Na₂CO₃, pH 10,87° C. 3.5 33.5 181 TiOSO₄ + H₂O₂ + NH₄OH, 25° C., 15 hr, + Na₂SO₄, pH3, 85° C., 4 hr 3.5 29.8 182 TiOSO₄ + H₂O₂ + NaOH, pH 4.1, 25° C., 15hr, remove Na, 90° C., 1.5 hr 3.5 31.3 183 TiOSO₄ + H₂O₂ + NaNO₃ +Na₂SO₄ + NaOH, pH 4, 56° C., 15 hr 3.5 60.7 184 TiOSO₄ + H₂O₂ + NaNO₃ +Na₂SO₄ + NaOH, pH 3.8, 70° C., 5.5 hr 3.5 93.6 185 TiOSO₄ + H₂O₂ +KNO₃ + KOH, pH 3.5, 90° C., 1.5 hr 3.5 44.1 K/Ti 186 TiOSO₄ + H₂O₂ +Na₂SO₄ + NaOH, pH 3.6, 83° C., 2 hr 3.5 177.6 187 TiOSO₄ + H₂O₂ + NaNO₃,pH <1, 88° C., 4 hr 3.5 19.5 188 TiOSO₄ + H₂O₂ + NaNO₃ + NaOH, pH 4.7,88° C., 2 hr 3.5 27.0 189 TiOSO₄ + H₂O₂ + Na₂CO₃, pH 3.3, 85° C., 1.5 hr15 5.5 190 TiOSO₄ + H₂O₂ + Na₂CO₃, pH 8.3, 80° C., 3 hr 10 14.1 191TiOSO₄ + NaOH + NaNO₃, pH 6.2, 90° C., 1.5 hr 2.0 25.4 192 TiOSO₄ + 1H₂O₂ + NaOH, pH 4.4, 90° C., 5 hr 3.4 7.1 193 Ti(OiPr)₄ + 2 Oxalate +H₂O₂ + NH₄Cl, pH 8.1, 90° C., 1.5 hr 3.5 0.0 194 Ti(OiPr)₄ + 1 Oxalate +H₂O₂ + NH₄Cl, pH 8.1, 90° C., 1.5 hr 3.5 0.0 195 Ti(OiPr)₄ + Oxalate +H₂O₂ + NH₄CO₃, pH 8.7, 92° C., 1.5 hr 3.5 10.3 Li/Ti Induction TotalCatalyst Time Time Productivity Activity HLMI I₁₀ MI HLMI/ Example g minmin gPE/gCat gPE/g/h g/10 min g/10 min g/10 min MI 158 0.0994 15.0 72.52948 3076 4.0 0.60 0 159 0.1036 20.0 99.5 3089 2331 4.0 0.55 0 1600.1758 5.0 35.0 1809 3618 38.6 9.3 0.74 52.1 161 0.0478 6.0 63.0 50635329 16.2 3.4 0.15 162 0.0561 7.0 66.0 3440 3499 8.3 1.5 NA 163 0.047512.0 73.0 2926 2878 24.2 5.1 0.27 91.3 164 0.0684 12.0 73.0 2997 294826.9 5.8 0.36 74.5 165 0.0474 15.0 72.0 1920 2021 8.5 1.6 0.04 203.6 1660.0557 4.0 83.0 2926 2223 13.6 2.7 0.11 124.9 167 0.0514 7.0 64.0 33073481 5.2 0.8 NA 168 0.0884 10.0 70.0 2387 2387 2.4 0.4 0.004 543.3 1690.0667 8.0 85.0 2264 1764 10.4 1.9 0.059 175.2 170 0.1033 8.8 62.1 29243289 5.8 1.0 NA 171 0.117 17.0 100.0 598 432 62.5 14.8 1.09 57.5 1720.1127 10.0 70.0 1624 1624 3.1 0.3 0.00 2447 173 0.1161 6.0 64.0 22392317 31.4 6.7 0.37 84.5 174 0.063 13.0 85.0 2556 2130 39.7 8.8 0.59 67.2175 0.0478 43.0 66.0 481 1255 21.0 4.3 0.22 93.6 176 0.0545 31.0 81.01028 1233 0.0 0.0 0.00 177 0.0818 10.0 53.9 2941 4023 26.5 5.3 0.28 95178 0.1022 8.3 64.5 3006 3207 13.8 2.9 0.11 125 179 0.0849 9.3 53.7 30254080 12.4 2.4 0.08 155 180 0.0788 15.6 86.7 3055 2580 34.1 7.5 0.47 73181 0.0769 13.5 69.2 3155 3396 12.9 2.4 0.08 161 182 0.0978 10.2 65.03061 3352 17.4 3.2 0.13 134 183 0.0702 11.1 60.2 2896 3541 32.4 6.9 0.4375 184 0.0833 9.8 69.4 2938 2956 35.2 7.9 0.55 64 185 0.0963 11.8 77.03193 2940 22.1 4.6 0.23 96 186 0.0837 17.2 76.7 3102 3125 27.5 6.0 0.3579 187 0.0801 11.0 68.7 2954 3072 4.2 0.6 NA 188 0.0853 10.3 55.8 31074097 32.4 6.9 0.41 79 189 0.0709 13.7 75.6 3061 2964 21.2 4.5 0.29 73190 0.0833 16.1 74.9 1100 1121 38.0 8.6 0.60 63 191 0.0779 16.9 78.13140 3077 30.3 6.6 0.43 71 192 0.1023 10.0 76.7 3319 2988 6.4 1.0 NA 1930.0642 9.2 64.6 3117 3374 21.9 4.4 0.21 104 194 0.0826 7.5 68.5 30993045 18.9 3.7 0.24 79 195 0.0569 14.2 66.0 3099 3045 44.7 9.34 0.55 81Example Cr Na Ti K Calcined 173 1.16% 0.49% 0.58% Yes 174 1.26% 0.94%2.10% Yes 180 1.19% 0.12% 0.76% Yes 181 1.06% 0.10% 1.94% No 182 1.29%0.47% 2.11% No 183 1.01% 1.35% 3.14% Yes 183 0.64% 0.50% 2.94% No 1841.01% 0.14% 3.53% Yes 184 0.88% 1.11% 4.42% No 185 1.02% 0.00% 4.75%0.91% No 186 0.82% 0.42% 3.89% No 187 0.98% 0.01% 2.69% No 188 0.75%0.41% 3.22% No 190 1.01% 1.88% 9.58% 0.01% No 191 1.30% 1.01% 2.50% No192 1.32% 0.04% 1.41% No

The invention is described above with reference to numerous aspects andspecific examples. Many variations will suggest themselves to thoseskilled in the art in light of the above detailed description. All suchobvious variations are within the full intended scope of the appendedclaims. Other aspects of the invention can include, but are not limitedto, the following (aspects are described as “comprising” but,alternatively, can “consist essentially of” or “consist of”):

Aspect 1. A titanated silica support comprising silica, from 0.1 to 10wt. % titanium, from 0.5 to 12 wt. % water, less than or equal to 2 wt.% carbon, and an alkali metal and/or zinc at a molar ratio of alkalimetal:titanium or zinc:titanium from 0.02:1 to 3:1 and/or at an amountin a range from 0.01 to 2 mmol of alkali metal or zinc per gram of thesilica.

Aspect 2. A titanated chromium/silica pre-catalyst comprising silica,from 0.1 to 5 wt. % chromium, from 0.1 to 10 wt. % titanium, from 0.5 to12 wt. % water, less than or equal to 4 wt. % carbon, and an alkalimetal and/or zinc at a molar ratio of alkali metal:titanium orzinc:titanium from 0.02:1 to 3:1 and/or at an amount in a range from0.01 to 2 mmol of alkali metal or zinc per gram of the silica.

Aspect 3. The pre-catalyst defined in aspect 2, wherein at least 75 wt.%, at least 80 wt. %, at least 90 wt. %, or at least 95 wt. %, of thechromium is present in an oxidation state of three or less.

Aspect 4. The support or pre-catalyst defined in any one of thepreceding aspects, wherein the support or the pre-catalyst contains anysuitable amount of carbon or an amount in any range disclosed herein,e.g., less than or equal to 3 wt. %, less than or equal to 2 wt. %, lessthan or equal to 1 wt. %, less than or equal to 0.5 wt. %, less than orequal to 0.3 wt. %, or less than or equal to 0.1 wt. %, based on thetotal weight of the respective support or pre-catalyst.

Aspect 5. The support or pre-catalyst defined in any one of thepreceding aspects, wherein the support or the pre-catalyst contains anysuitable amount of water/moisture or an amount in any range disclosedherein, e.g., from 0.5 to 12 wt. %, from 1 to 11 wt. %, from 2.5 to 10wt. %, from 3 to 9 wt. %, or from 5 to 8 wt. %, based on the totalweight of the respective support or pre-catalyst.

Aspect 6. A titanated chromium/silica catalyst comprising silica, from0.1 to 5 wt. % chromium, from 0.1 to 10 wt. % titanium, and an alkalimetal and/or zinc at a molar ratio of alkali metal:titanium orzinc:titanium from 0.02:1 to 3:1 and/or at an amount in a range from0.01 to 2 mmol of alkali metal or zinc per gram of the silica, whereinat least 60 wt. % of the chromium is present in an oxidation state of+6.

Aspect 7. A titanated chromium/silica catalyst comprising silica, from0.1 to 5 wt. % chromium, and from 0.1 to 10 wt. % titanium, wherein atleast 60 wt. % of the chromium is present in an oxidation state of +6,and the catalyst is characterized by a HLMI (g/10 min) of the polymerthat is greater than the equation Y(HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983), wherein x is the number oftitanium atoms per square nanometer of silica surface area for thetitanated chromium/silica catalyst.

Aspect 8. The catalyst defined in aspect 7, wherein the catalyst furthercomprises an alkali metal and/or zinc at a molar ratio of alkalimetal:titanium or zinc:titanium from 0.02:1 to 3:1, and/or an alkalimetal and/or zinc at an amount in a range from 0.01 to 2 mmol of alkalimetal or zinc per gram of the silica.

Aspect 9. The catalyst defined in any one of aspects 6-8, wherein atleast 70 wt. %, at least 75 wt. %, at least 80 wt. %, at least 85 wt. %,at least 90 wt. %, or at least 95 wt. 00 of the chromium is present inan oxidation state of +6.

Aspect 10. The catalyst defined in any one of aspects 6-9, wherein thecatalyst is characterized by a HLMI (g/10 min) of the polymer that isgreater than the equation Y (HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983),wherein x is the number of titanium atoms per square nanometer of silicasurface area for the titanated chromium/silica catalyst; alternatively,Y=1.1*(−9.6153x³+21.088x²+25.835x+5.7983); alternatively,Y=1.15*(−9.6153x³+21.088x²+25.835x+5.7983); alternatively,Y=1.2*(−9.6153x³+21.088x²+25.835x+5.7983); or alternatively,Y=1.3*(−9.6153x³+21.088x²+25.835x+5.7983).

Aspect 11. The catalyst defined in any one of aspects 6-10, wherein thecatalyst contains any suitable amount of water/moisture or an amount inany range disclosed herein, less than or equal to 3 wt. %, less than orequal to 2 wt. %, less than or equal to 1.5 wt. %, less than or equal to1 wt. %, or less than or equal to 0.5 wt. %, based on the total weightof the catalyst.

Aspect 12. The catalyst or pre-catalyst defined in any one of aspects2-11, wherein the catalyst contains any suitable amount of the chromiumor an amount in any range disclosed herein, e.g., from 0.3 to 3 wt. %,from 0.4 to 2 wt. %, from 0.5 to 1.5 wt. %, or from 0.7 to 1.5 wt. %,based on the total weight of the respective catalyst.

Aspect 13. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, the pre-catalyst, or thecatalyst contains any suitable amount of the titanium or an amount inany range disclosed herein, e.g., from 0.5 to 7 wt. %, from 0.5 to 3 wt.%, from 0.8 to 2 wt. %, from 1 to 6 wt. %, or from 1.5 to 4 wt. %, basedon the total weight of the respective support, pre-catalyst, orcatalyst.

Aspect 14. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, pre-catalyst, or thecatalyst contains any suitable amount of nitrogen or an amount in anyrange disclosed herein, e.g., from 0.01 to 1.5 wt. %, from 0.1 to 1.5wt. %, from 0.3 to 1 wt. %, from 0.4 to 1.2 wt. %, from 0.4 to 1 wt. %,or from 0.5 to 0.7 wt. %, based on the total weight of the respectivesupport, pre-catalyst, or catalyst.

Aspect 15. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, pre-catalyst, or thecatalyst contains any suitable amount of the alkali metal or zinc, or anamount in any range disclosed herein, e.g., a minimum molar ratio ofalkali metal:titanium or zinc:titanium of 0.02:1, 0.05:1, 0.08:1, 0.1:1,0.12:1, 0.15:1, or 0.2:1, and a maximum molar ratio 3:1, 2.5:1, 2.2:1,2:1, or 1.8:1, and the molar ratio can range from any minimum molarratio to any maximum ratio disclosed herein.

Aspect 16. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, pre-catalyst, or thecatalyst contains any suitable amount of the alkali metal or zinc, or anamount in any range disclosed herein, e.g., a minimum amount of thealkali metal or zinc per gram of silica of 0.01, 0.02, 0.04, 0.08, 0.1,0.11, 0.13, or 0.15 mmol/g, and a maximum amount of 2, 1.5, 1.2, 1, 0.9,or 0.8 mmol/g, and the amount in mmol/g can range from any minimumamount to any maximum amount disclosed herein.

Aspect 17. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, pre-catalyst, or thecatalyst comprises the alkali metal.

Aspect 18. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, pre-catalyst, or thecatalyst comprises zinc.

Aspect 19. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the alkali metal comprises lithium,sodium, potassium, or a combination thereof; alternatively, lithium;alternatively, sodium; or alternatively, potassium.

Aspect 20. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the titanium is adsorbed onto the silica.

Aspect 21. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein at least a portion of the zinc or thealkali metal is bound (chemically) to the titanium.

Aspect 22. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein at least a portion of the zinc and thetitanium is present as zinc titanate and/or at least a portion of thealkali metal and the titanium is present as an alkali metal titanate,e.g., sodium titanate.

Aspect 23. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, the pre-catalyst, or thecatalyst contains any suitable amount of the silica or an amount in anyrange disclosed herein, e.g., from 70 to 99.5 wt. %, from 80 to 98 wt.%, from 80 to 95 wt. %, from 85 to 98 wt. %, from 85 to 95 wt. %, from90 to 99.5 wt. %, or from 90 to 98 wt. %, based on the total weight ofthe respective support, pre-catalyst, or catalyst.

Aspect 24. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, the pre-catalyst, or thecatalyst has a pore volume (total) in any suitable range, or any rangedisclosed herein, e.g., from 0.5 to 3 mL/g, from 0.8 to 2.5 mL/g, from 1to 2 mL/g, or from 1.3 to 1.8 mL/g.

Aspect 25. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support, the pre-catalyst, or thecatalyst has a BET surface area in any suitable range, or any rangedisclosed herein, e.g., from 100 to 700 m²/g, from 150 to 650 m²/g, from200 to 600 m²/g, or from 250 to 550 m²/g.

Aspect 26. The support, pre-catalyst, or catalyst defined in any one ofthe preceding aspects, wherein the support or the catalyst has anaverage (d50) particle size in any suitable range, or any rangedisclosed herein, e.g., from 15 to 350 μm, from 25 to 300 μm, from 50 to200 μm, or from 75 to 150 μm.

Aspect 27. An olefin polymerization process, the process comprisingcontacting the titanated chromium/silica catalyst defined in any one ofaspects 6-26 and an optional co-catalyst with an olefin monomer and anoptional olefin comonomer in a polymerization reactor system underpolymerization conditions to produce an olefin polymer.

Aspect 28. The olefin polymerization process defined in aspect 27,wherein a co-catalyst is used, and the co-catalyst comprises anysuitable co-catalyst or any co-catalyst disclosed herein, e.g., analuminoxane co-catalyst, an organoaluminum co-catalyst, or anorganoboron co-catalyst, or any combination thereof.

Aspect 29. The olefin polymerization process defined in aspect 27 or 28,wherein the olefin monomer comprises any olefin monomer disclosedherein, e.g., any C₂-C₂₀ olefin.

Aspect 30. The olefin polymerization process defined in any one ofaspects 27-29, wherein the olefin monomer and the optional olefincomonomer independently comprise a C₂-C₂₀ alpha-olefin.

Aspect 31. The olefin polymerization process defined in any one ofaspects 27-30, wherein the olefin monomer comprises ethylene.

Aspect 32. The olefin polymerization process defined in any one ofaspects 27-31, wherein the titanated chromium/silica catalyst iscontacted with ethylene and an olefin comonomer comprising a C₃-C₁₀alpha-olefin.

Aspect 33. The olefin polymerization process defined in any one ofaspects 27-32, wherein the titanated chromium/silica catalyst iscontacted with ethylene and an olefin comonomer comprising 1-butene,1-hexene, 1-octene, or a mixture thereof.

Aspect 34. The olefin polymerization process defined in any one ofaspects 27-33, wherein the polymerization reactor system comprises abatch reactor, a slurry reactor, a gas-phase reactor, a solutionreactor, a high pressure reactor, a tubular reactor, an autoclavereactor, or a combination thereof.

Aspect 35. The olefin polymerization process defined in any one ofaspects 27-33, wherein the polymerization reactor system comprises aslurry reactor, a gas-phase reactor, a solution reactor, or acombination thereof.

Aspect 36. The olefin polymerization process defined in any one ofaspects 27-35, wherein the polymerization reactor system comprises aloop slurry reactor.

Aspect 37. The olefin polymerization process defined in any one ofaspects 27-36, wherein the polymerization reactor system comprises asingle reactor.

Aspect 38. The olefin polymerization process defined in any one ofaspects 27-36, wherein the polymerization reactor system comprises 2reactors.

Aspect 39. The olefin polymerization process defined in any one ofaspects 27-36, wherein the polymerization reactor system comprises morethan 2 reactors.

Aspect 40. The olefin polymerization process defined in any one ofaspects 27-39, wherein the olefin polymer comprises any olefin polymerdisclosed herein.

Aspect 41. The olefin polymerization process defined in any one ofaspects 27-40, wherein the olefin polymer comprises an ethylenehomopolymer, an ethylene/1-butene copolymer, an ethylene/1-hexenecopolymer, and/or an ethylene/1-octene copolymer.

Aspect 42. The olefin polymerization process defined in any one ofaspects 27-41, wherein the polymerization conditions comprise apolymerization reaction temperature in a range from 60° C. to 120° C.and a reaction pressure in a range from 200 to 1000 psig (from 1.4 to6.9 MPa).

Aspect 43. The olefin polymerization process defined in any one ofaspects 27-42, wherein the polymerization conditions are substantiallyconstant, e.g., for a particular polymer grade.

Aspect 44. The olefin polymerization process defined in any one ofaspects 27-43, wherein no hydrogen is added to the polymerizationreactor system.

Aspect 45. The olefin polymerization process defined in any one ofaspects 27-43, wherein hydrogen is added to the polymerization reactorsystem.

Aspect 46. The olefin polymerization process defined in any one ofaspects 27-45, wherein the olefin polymer has a density in any rangedisclosed herein, e.g., from 0.92 to 0.965, from 0.93 to 0.96, from0.935 to 0.955, or from 0.94 to 0.95 g/cm³.

Aspect 47. The olefin polymerization process defined in any one ofaspects 27-46, wherein the olefin polymer has a MI in any rangedisclosed herein, e.g., from 0 to 100, from 0.1 to 10, from 0.2 to 5, orfrom 0.25 to 2 g/10 min.

Aspect 48. The olefin polymerization process defined in any one ofaspects 27-47, wherein the olefin polymer has a HLMI in any rangedisclosed herein, e.g., from 1 to 1000, from 5 to 500, from 6 to 40,from 8 to 60, from 10 to 100, or from 12 to 50 g/10 min.

Aspect 49. The olefin polymerization process defined in any one ofaspects 27-48, wherein the olefin polymer has a ratio of Mw/Mn in anyrange disclosed herein, e.g., from 5 to 30, from 7 to 25, from 9 to 20,from 10 to 25, or from 10 to 15.

Aspect 50. The olefin polymerization process defined in any one ofaspects 27-49, wherein the olefin polymer has a Mw in any rangedisclosed herein, e.g., from 10 to 500, from 30 to 300, from 50 to 400,from 50 to 250, from 80 to 200, or from 100 to 250 kg/mol.

Aspect 51. The olefin polymerization process defined in any one ofaspects 27-50, wherein the olefin polymer has a Mn in any rangedisclosed herein, from 1 to 50, from 3 to 30, from 4 to 40, from 5 to25, or from 8 to 20 kg/mol.

Aspect 52. The olefin polymerization process defined in any one ofaspects 27-51, wherein the olefin polymer has a CY-a parameter in anyrange disclosed herein, e.g., from 0.05 to 0.5, from 0.08 to 0.4, from0.1 to 0.3, from 0.1 to 0.25, or from 0.15 to 0.25.

Aspect 53. The olefin polymer produced by the olefin polymerizationprocess defined in any one of aspects 27-52.

Aspect 54. An article of manufacture comprising the polymer defined inaspect 53.

Aspect 55. The article defined in aspect 54, wherein the article is anagricultural film, an automobile part, a bottle, a drum, a fiber orfabric, a food packaging film or container, a food service article, afuel tank, a geomembrane, a household container, a liner, a moldedproduct, a medical device or material, a pipe, a sheet or tape, or atoy.

Aspect 56. A process for preparing a titanated silica support, theprocess comprising: (i) contacting water, a peroxide compound, and atitanium precursor to form a first mixture, (ii) contacting a silicawith the first mixture under conditions sufficient for titanium toadsorb onto the silica and form a second mixture, (iii) isolating asolid fraction from the second mixture, and (iv) drying the solidfraction to form the titanated silica support.

Aspect 57. A process for preparing a titanated silica support, theprocess comprising: (a) contacting water, hydrogen peroxide, an alkalimetal precursor and/or a zinc precursor, a nitrogen-containing compound,and a titanium precursor to form a first mixture, (b) contacting asilica with the first mixture under conditions sufficient for titaniumto adsorb onto the silica and form a second mixture, (c) subjecting thesecond mixture to a reaction temperature in a range from 40 to 100° C.,(d) isolating a solid fraction from the second mixture and washing thesolid fraction, and (e) drying the solid fraction to form the titanatedsilica support.

Aspect 58. A process for preparing a titanated silica support, theprocess comprising: (A) contacting water, hydrogen peroxide, an alkalimetal precursor and/or a zinc precursor, and a titanium precursor toform a first mixture, (B) contacting a silica with the first mixtureunder conditions sufficient for titanium to adsorb onto the silica andform a second mixture, (C) subjecting the second mixture to a reactiontemperature in a range from 40 to 100° C., (D) isolating a solidfraction from the second mixture and washing the solid fraction, and (E)drying the solid fraction to form the titanated silica support.

Aspect 59. The process defined in any one of aspects 56-58, wherein thefirst mixture is formed by contacting the materials in any order orsequence.

Aspect 60. The process defined in any one of aspects 56-59, wherein amolar ratio of the peroxide compound or hydrogen peroxide to titanium isin any suitable range or any range disclosed herein, e.g., from 0.5:1 to100:1, from 2:1 to 50:1, from 3:1 to 20:1, or from 5:1 to 11:1.

Aspect 61. The process defined in any one of aspects 56-60, wherein amolar ratio of the alkali metal or zinc to titanium is in any suitablerange or any range disclosed herein, e.g., from 0.1:1 to 300:1, such asfrom 0.2:1 to 100:1, from 0.5:1 to 20:1, from 0.7:1 to 10:1, from 1:1 to5:1, or from 1:1 to 3:1.

Aspect 62. The process defined in any one of aspects 56-61, wherein aweight ratio of titanium to water (Ti:H₂O) is in any suitable range orany range disclosed herein, e.g., from 0.0001:1 to 0.02:1, from 0.001:1to 0.02:1, from 0.005:1 to 0.02:1, or from 0.03:1 to 0.07:1.

Aspect 63. The process defined in any one of aspects 56-62, wherein thetitanium precursor comprises any suitable titanium compound or anytitanium compound disclosed herein, e.g., a Ti (III) compound, a Ti (IV)compound, or any combination thereof.

Aspect 64. The process defined in any one of aspects 56-62, wherein thetitanium precursor comprises a titanium carboxylate (e.g., titaniumoxalate, titanium glycolate, titanium lactate, titanium citrate,titanium malate), a titanium halide, a titanium oxide, a titaniumhydroxide, a titanium alkoxide (e.g., titanium isopropoxide, titaniumn-propoxide), a titanium sulfate, a titanium nitrate, or any combinationthereof.

Aspect 65. The process defined in any one of aspects 56-62, wherein thetitanium precursor comprises TiOSO₄, Ti(OH)₄, Ti metal, Ti(OR)₄,TiO(OH)₂, or any combination thereof.

Aspect 66. The process defined in any one of aspects 56-65, furthercomprising a step of adjusting a pH of the first mixture to within anysuitable range or any range disclosed herein, e.g., from 3 to 12, from 3to 10, from 4 to 12, from 4 to 10, or from 6 to 10, prior to contactingthe silica with the first mixture.

Aspect 67. The process defined in any one of aspects 57-66, wherein aweight ratio of the nitrogen-containing compound to titanium is in anysuitable range or any range disclosed herein, e.g., from 5:1 to 300:1,from 10:1 to 200:1, from 25:1 to 150:1, or from 50:1 to 100:1.

Aspect 68. The process defined in any one of aspects 56-67, wherein thesilica contains any suitable amount of water/moisture or an amount inany range disclosed herein, less than or equal to 25 wt. %, less than orequal to 20 wt. %, less than or equal to 15 wt. %, or less than or equalto 10 wt. %, based on the total weight of the silica.

Aspect 69. The process defined in any one of aspects 56-68, wherein thesilica is characterized by the pore volume, surface area, and averageparticle size defined in any one of aspects 24-26.

Aspect 70. The process defined in any one of aspects 56-67, wherein thesilica contains any suitable amount of water or an amount in any rangedisclosed herein, at least 50 wt. %, at least 60 wt. %, at least 70 wt.%, or at least 80 wt. %, such as a silica hydrogel.

Aspect 71. The process defined in any one of aspects 56-70, wherein thesilica is contacted with the first mixture at a weight ratio of thesilica to water (silica:H₂O) in any suitable range or any rangedisclosed herein, e.g., from 0.001:1 to 1:1, from 0.01:1 to 0.5:1, from0.05:1 to 0.4:1, or from 0.1:1 to 0.3:1.

Aspect 72. The process defined in any one of aspects 56-71, wherein thesecond mixture is subjected to a reaction temperature in any suitablerange or any range disclosed herein, e.g., from 50° C. to 100° C., from60° C. to 100° C., from 70° C. to 100° C., or from 80° C. to 100° C.

Aspect 73. The process defined in any one of aspects 56-72, wherein thesecond mixture is subjected to a reaction temperature for any suitableperiod of time or a period of time in any range disclosed herein, e.g.,from 10 min to 4 days, from 20 min to 2 days, from 30 min to 24 hr, orfrom 40 min to 2 hr.

Aspect 74. The process defined in any one of aspects 56-73, whereinisolating the solid fraction comprises any suitable separationstechnique or any technique disclosed herein, e.g., filtering, settling,decanting, pressing, centrifuging, cycloning, hydrocycloning, or anycombination thereof.

Aspect 75. The process defined in any one of aspects 56-74, whereinwashing the solid fraction comprising any suitable wash solution or anywash solution disclosed herein, e.g., water, an alcohol (e.g., ethanol),or a mixture thereof.

Aspect 76. The process defined in any one of aspects 56-75, whereindrying is conducted at any suitable temperature or a temperature in anyrange disclosed herein, e.g., from 25° C. to 200° C., from 50° C. to150° C., from 70° C. to 120° C., or from 90° C. to 110° C.

Aspect 77. The process defined in any one of aspects 56-76, whereindrying is conducted for any suitable period of time or a period of timein any range disclosed herein, e.g., from 1 sec to 1 day, from 1 hr to12 hr, from 2 hr to 8 hr, or from 0.1 to 5 sec.

Aspect 78. The process defined in any one of aspects 56-77, whereindrying comprises spray drying, tray drying, flash drying, freeze drying,oven drying, microwave drying; alternatively, spray drying; oralternatively, flash drying.

Aspect 79. The titanated silica support prepared by the process definedin any one of aspects 56-78.

Aspect 80. The titanated silica support prepared by the process definedin any one of aspects 56-78, wherein the titanated silica support isdefined by any one of aspects 1-26.

Aspect 81. A process for preparing a titanated chromium/silicapre-catalyst, the process comprising: performing the process forpreparing a titanated silica support defined in any one of aspects56-78, and contacting a chromium precursor with the first mixture or thesecond mixture in any step prior to the step of isolating the solidfraction from the second mixture.

Aspect 82. A process for preparing a titanated chromium/silicapre-catalyst, the process comprising: performing the process forpreparing a titanated silica support defined in any one of aspects56-78, and contacting a chromium precursor with the solid fraction afterisolating the solid fraction from the second mixture (before or afterdrying the solid fraction).

Aspect 83. The process defined in aspect 81 or 82, wherein the chromiumprecursor comprises any suitable chromium compound or any chromiumcompound disclosed herein, e.g., a chromium (II) compound, a chromium(III) compound, or any combination thereof.

Aspect 84. The process defined in any one of aspects 81-83, wherein thechromium precursor comprises chromium trioxide, chromium acetate,chromium hydroxy acetate, chromium nitrate, or any combination thereof.

Aspect 85. The process defined in any one of aspects 81-84, wherein thechromium precursor is soluble in water.

Aspect 86. A process for preparing a titanated chromium/silicapre-catalyst, the process comprising: performing the process forpreparing a titanated silica support defined in any one of aspects56-78, except instead of contacting the silica with the first mixture,contacting a chromium/silica pre-catalyst with the first mixture.

Aspect 87. The titanated chromium/silica pre-catalyst produced by theprocess defined in any one of aspects 81-86.

Aspect 88. The titanated chromium/silica pre-catalyst produced by theprocess defined in any one of aspects 81-86, wherein the titanatedchromium/silica pre-catalyst is defined by any one of aspects 2-26.

Aspect 89. A process for preparing a titanated chromium/silica catalyst,the process comprising: performing the process for preparing a titanatedchromium/silica pre-catalyst defined in any one of aspects 81-86, andactivating the titanated chromium/silica pre-catalyst to form the(activated) titanated chromium/silica catalyst.

Aspect 90. The process defined in aspect 89, wherein activatingcomprises any suitable temperature and time conditions or anytemperature and time conditions disclosed herein, e.g., from 400° C. to900° C., from 500° C. to 850° C., from 600° C. to 800° C., or from 600°C. to 700° C., for a time period of from 1 min to 24 hr, from 1 hr to 12hr, from 2 hr to 8 hr, or from 2 hr to 6 hr.

Aspect 91. The titanated chromium/silica catalyst produced by theprocess defined in aspect 89 or 90.

Aspect 92. The titanated chromium/silica catalyst produced by theprocess defined in aspect 89 or 90, wherein the titanatedchromium/silica catalyst is defined by any one of aspects 6-26.

We claim:
 1. A titanated silica support comprising: silica; from 0.1 to10 wt. % titanium; from 0.5 to 12 wt. % water; less than or equal to 4wt. % carbon; and an alkali metal and/or zinc at a molar ratio of alkalimetal:titanium or zinc:titanium from 0.02:1 to 3:1 and/or at an amountin a range from 0.01 to 2 mmol of alkali metal or zinc per gram of thesilica.
 2. The support of claim 1, wherein the support comprises lessthan or equal to 2 wt. % carbon.
 3. The support of claim 1, wherein themolar ratio of alkali metal:titanium or zinc:titanium is from 0.12:1 to2.2:1 and/or the amount of the alkali metal or zinc is in a range from0.1 to 1.2 mmol of alkali metal or zinc per gram of the silica.
 4. Thesupport of claim 1, wherein the support comprises the alkali metal andthe alkali metal comprises sodium.
 5. The support of claim 4, wherein:at least a portion of the sodium is bound to the titanium; and/or atleast a portion of the sodium is present as sodium titanate.
 6. Atitanated chromium/silica pre-catalyst comprising: the titanated silicasupport of claim 1; and from 0.1 to 5 wt. % chromium.
 7. Thepre-catalyst of claim 6, wherein at least 75 wt. % of the chromium ispresent in an oxidation state of three or less.
 8. The pre-catalyst ofclaim 6, wherein the pre-catalyst further comprises from 0.01 to 1.5 wt.% nitrogen.
 9. A titanated chromium/silica catalyst comprising: silica;from 0.1 to 5 wt. % chromium; from 0.1 to 10 wt. % titanium; and analkali metal and/or zinc at a molar ratio of alkali metal:titanium orzinc:titanium from 0.02:1 to 3:1 and/or at an amount in a range from0.01 to 2 mmol of alkali metal or zinc per gram of the silica; whereinat least 60 wt. % of the chromium is present in an oxidation state of+6.
 10. The catalyst of claim 9, wherein the catalyst is characterizedby a HLMI (g/10 min) of a polymer that is greater than the equation Y(HLMI)=(−9.6153x³+21.088x²+25.835x+5.7983), wherein x is the number oftitanium atoms per square nanometer of silica surface area for thetitanated chromium/silica catalyst.
 11. The catalyst of claim 9, whereinthe titanium is adsorbed onto the silica.
 12. An olefin polymerizationprocess, the process comprising contacting the titanated chromium/silicacatalyst of claim 9 and an optional co-catalyst with an olefin monomerand an optional olefin comonomer in a polymerization reactor systemunder polymerization conditions to produce an olefin polymer.
 13. Aprocess for preparing a titanated silica support, the processcomprising: (i) contacting water, a peroxide compound, and a titaniumprecursor to form a first mixture; (ii) contacting a silica with thefirst mixture under conditions sufficient for titanium to adsorb ontothe silica and form a second mixture; (iii) isolating a solid fractionfrom the second mixture; and (iv) drying the solid fraction to form thetitanated silica support.
 14. The process of claim 13, wherein: step (i)comprises contacting water, hydrogen peroxide, an alkali metal precursorand/or a zinc precursor, a nitrogen-containing compound, and thetitanium precursor to form the first mixture; the second mixture issubjected to a reaction temperature in a range from 40 to 100° C. beforeisolating the solid fraction; and the solid fraction is washed beforedrying the solid fraction.
 15. The process of claim 14, wherein: thesilica is a preformed silica; and the alkali metal precursor iscontacted in step (i) and the alkali metal precursor comprises sodium.16. The process of claim 13, wherein: step (i) comprises contactingwater, hydrogen peroxide, an alkali metal precursor and/or a zincprecursor, and the titanium precursor to form the first mixture; thesecond mixture is subjected to a reaction temperature in a range from 40to 100° C. before isolating the solid fraction; and the solid fractionis washed before drying the solid fraction.
 17. The process of claim 16,wherein: the silica is a preformed silica; and the alkali metalprecursor is contacted in step (i) and the alkali metal precursorcomprises sodium.
 18. The process of claim 13, wherein the processfurther comprises a step of adjusting a pH of the first mixture towithin a range from 3 to 12, prior to contacting the silica with thefirst mixture.
 19. A process for preparing a titanated chromium/silicapre-catalyst, the process comprising: performing the process forpreparing a titanated silica support of claim 13; and contacting achromium precursor with the first mixture or the second mixture in anystep prior to the step of isolating the solid fraction from the secondmixture.
 20. A process for preparing a titanated chromium/silicapre-catalyst, the process comprising: performing the process forpreparing a titanated silica support of claim 13; and contacting achromium precursor with the solid fraction after isolating the solidfraction from the second mixture.
 21. A process for preparing atitanated chromium/silica pre-catalyst, the process comprising:performing the process for preparing a titanated silica support of claim13, except instead of contacting the silica with the first mixture,contacting a chromium/silica pre-catalyst with the first mixture.
 22. Aprocess for preparing a titanated chromium/silica catalyst, the processcomprising: performing the process for preparing a titanatedchromium/silica pre-catalyst of claim 19; and activating the titanatedchromium/silica pre-catalyst to form the titanated chromium/silicacatalyst.